Landscaping a page

Question

I am trying to landscape a specific page of my document and used pdflscape package and landscape environment to do so. The page does turn into landscape mode, however, the texts are not (as shown in the figure). What does make the page to be like that?

Here I add the main.tex file and try.sty file of my document.

\documentclass[oneside,12pt,a4paper,fleqn]{book}
\usepackage{try}
\begin{document}
\frontmatter
\mainmatter
   \input{CompleteGraph.tex}
\backmatter
\end{document}

This is the try.sty file.

% LaTeX cod for chapter header
%--------------------------------------------------------
\makeatletter
\def\@makechapterhead#1{
  %\vspace*{20\p@}   %  \vspace*{15\p@}
  {\parindent \z@ 
      \centering  
    \normalfont
    \ifnum \c@secnumdepth >\m@ne
      \if@mainmatter
      \normalsize 
           \bfseries \@chapapp\space \thechapter 
       \par\nobreak
              \vskip 1.4\baselineskip 
      \fi
    \fi
    \interlinepenalty\@M
    \normalsize     
         \bfseries #1\par\nobreak 
       \vskip 1.4\baselineskip %
  }}
\def\@schapter#1{\if@twocolumn
                   \@topnewpage[\@makeschapterhead{#1}]%
                 \else
                   \@makeschapterhead{#1}
                   \@afterheading
                 \fi}
\def\@makeschapterhead#1{
  %\vspace*{20\p@} % \vspace*{20\p@} %
  {\parindent \z@  
    \centering  
    \normalfont 
    \interlinepenalty\@M
    \normalsize 
    \bfseries  #1\par\nobreak
         \vskip 1.4\baselineskip  
  }}
\makeatother
\renewcommand{\chaptername}{CHAPTER}
%------------------------------------------------------------
% Commands for layout
   %\setlength{\topmargin}{-1.2cm}
   %\setlength{\oddsidemargin}{1.7cm}   %\setlength{\oddsidemargin}{1.46cm} 
\setlength{\textwidth}{14.5cm}
   \setlength{\textheight}{24.5cm} %  \setlength{\textheight}{24.5cm}
   %\setlength{\headheight}{2mm}
    %\setlength{\headsep}{10.175mm}
%-------------------------------------------------------------
% Command for 1.5 spacing
   %\renewcommand{\baselinestretch}{1.5}
\usepackage{doublespace}
\setstretch{1.5}
%-------------------------------------------------------------
% Command for  indentation
   \setlength\parindent{.5in}
   \usepackage{indentfirst} %1st line indented after section...
%-------------------------------------------------------------
% Command for space between paragraph
  \makeatletter
    %\setlength{\parskip}{1.5\baselineskip \@plus 3ex
                %  \@minus 2.0ex}
    \setlength{\parskip}{2\baselineskip \@plus .01ex
                  \@minus .01ex}
   \makeatother
%-------------------------------------------------------------
% Commands for no hyphenation and right justified
    \hyphenpenalty=10000 \sloppy
    \raggedbottom
%-------------------------------------------------------------
% Command to get rid of default running head
   \pagestyle{myheadings}
%-------------------------------------------------------------
% Command for  page number 
%  \makeatletter
%    \renewcommand{\ps@plain}{%
%    \renewcommand{\@oddhead}{\hfill\textrm{\thepage}}
%    \renewcommand{\@evenhead}{\@oddhead}
%    \renewcommand{\@evenfoot}{}
%    \renewcommand{\@oddfoot}{}  }
%   \makeatother
%-----------------------------------------------------------------
%For section font
 % \usepackage{sectsty} 
  %  \chapterfont{\centering\normalsize\uppercase}
  %  \sectionfont{\normalsize\uppercase}
   % \subsectionfont{\normalsize}
   % \subsubsectionfont{\itshape\normalsize}
%---------------------------------------------------------
%--------------------------------------------------------------
% Commands for REFERENCES name
\renewcommand{\bibname}{REFERENCES}
%--------------------------------------------------------------
% Commands to change vertical space in section and subsection
\makeatletter
\renewcommand{\section}{@startsection
  {section}%      % the name
  {1}             % the level
  {0cm}           % the indent
  {1.0cm}         % the beforeskip
  {0.01cm}    %{0.5cm}    % the afterskip
  {\normalfont\normalsize\bfseries} } % the style
\renewcommand{\subsection}{@startsection
  {subsection}%   % the name
  {2}             % the leve2
  {0cm}           % the indent
  {1.0cm}         % the beforeskip
  {0.01cm} %{0.5cm}        % the afterskip
  {\normalfont\normalsize\bfseries} } % the style
\makeatother
%--------------------------------------------------------------
% Commands to change horizontal space in section and subsection
% for times romans
   \renewcommand{\thesection} % space between sect. etc.
     {\thechapter.\arabic{section}\hspace{.12in}}
    \renewcommand{\thesubsection} 
       {\thesection\hspace{-.3cm}.\arabic{subsection} \hspace{-.135cm}} 
%--------------------------------------------------------------
% Commands for  TocLoFT
  \usepackage{tocloft}
    %\cftsetrmarg{2.75cm} %

     \cftsetrmarg{1.5cm} %

       \cftsetpnumwidth{1.25cm} 
       %\cftsetpnumwidth{1.25cm}
    \renewcommand{\cftdot}{} % get rid of dots
%Table of Contents
\renewcommand{\contentsname}{}    % off tocname

\renewcommand{\cftchapfont}{\bfseries}
\renewcommand{\cftchappagefont}{\normalfont\bfseries}
\renewcommand{\cftchappresnum}{\hspace{0.3cm}CHAPTER }
%\setlength{\cftchapindent}{.8cm}      % chapter indent
\setlength{\cftsecindent}{2.3cm}      % section indent
\setlength{\cftsubsecindent}{3.25cm}  % subsection indent
\setlength{\cftchapnumwidth}{3.25cm}  % chp number width
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%  \renewcommand{\cftchapafterpnum}{\rule{1.75ex}{0ex}}
%   \renewcommand{\cftsecafterpnum}{\rule{1.75ex}{0ex}}
%   \renewcommand{\cftsubsecafterpnum}{\rule{1.75ex}{0ex}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  \renewcommand{\cftchapafterpnum}{\rule{0.75ex}{0ex}}
   \renewcommand{\cftsecafterpnum}{\rule{0.75ex}{0ex}}
   \renewcommand{\cftsubsecafterpnum}{\rule{0.75ex}{0ex}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%   \renewcommand{\cftchappagefont}{\normalfont}
%-------------------------------------------------------------

%List of Table
\setlength{\cfttabnumwidth}{2.5cm}  %\setlength{\cfttabnumwidth}{2.5cm}

\renewcommand{\listtablename}{} % off lotname
%\setlength{\cfttabindent}{-.015cm}      % table indent %%%%%%%%%%%%%%%%%%
\setlength{\cfttabindent}{-.1cm}      % table indent %%%%%%%%%%%%%%%%%%
\renewcommand{\cfttabpresnum}{Table }
\renewcommand{\cfttabafterpnum}{\rule{2ex}{0ex}}
\cftsetrmarg{3cm}
%------------------------------------------------------------
 %List of Figure
\setlength{\cftfignumwidth}{2.5cm}
\renewcommand{\listfigurename}{} % off lofname
\setlength{\cftfigindent}{-.1cm}      % figure indent %%%%%%%%%%%%%%%%%%
\renewcommand{\cftfigpresnum}{Figure }
\renewcommand{\cftfigafterpnum}{\rule{2ex}{0ex}}
%-------------------------------------------------------------
%-------------------------------------------------------------
% Command for bold caption
\makeatletter
  \long\def@makecaption#1#2{\vskip 10\p@   % caption parameter
       \setbox@tempboxa\hbox{{ #1,,,,,} #2} %%%%%
       \ifdim \wd@tempboxa >\hsize         % caption parameter
           {#1,,,,,}  #2\par  % caption parameter
       \else                                   % caption parameter
           \hbox to\hsize{\hfil\box@tempboxa\hfil}  % caption parameter
   \fi}                                            % caption parameter
\makeatother

\renewcommand{\thefigure}{\arabic{chapter}.\arabic{figure}}
\renewcommand{\thetable}{\arabic{chapter}.\arabic{table}}
%--------------------------------------------------------------
\usepackage{paralist} %refine list item
%--------------------------------------------------------------
\usepackage{latexsym,amsmath,amssymb} % math symbols
%--------------------------------------------------------------
\usepackage{graphicx} % .eps graphic
%--------------------------------------------------------------
\usepackage{pdflscape} % for landscape
%-------------------------------------------------------------- 
\usepackage{times}
%--------------------------------------------------------------
% Theorem-Like-Environment
\usepackage{theorem}
{\theorembodyfont{\upshape}
\newtheorem{lemma}{Lemma}[chapter]
\newtheorem{theorem}{\rule{0ex}{5ex}Theorem}[chapter]
\newtheorem{corollary}{Corollary}[chapter]
\newtheorem{proposition}{Proposition}[chapter]
\newtheorem{definition}{\rule{0ex}{5ex}Definition}[chapter]
\newtheorem{example}{Example}[chapter] }
%--------------------------------------------------------
\newenvironment{proof}{\begin{paragraph}
          {Proof}\vspace{-1cm}}{\end{paragraph}}
\newenvironment{solution}{\begin{paragraph}
          {Solution}\vspace{-1cm}}{\end{paragraph}}

and the CompleteGraph.tex file is just simple as follows.

\begin{landscape}
$COM\rightarrow$ a set of combinations of $\textrm{C}^{n}_{m}$\\
$(x_0\textrm{ }x_1\textrm{ }\cdots\textrm{ }x_m)\in COM$ such $x_i=0,1,2,...,n-1$ for $i=0,1,2,...,m$\
$\delta_j\rightarrow$ difference between two consecutive $x_i$\
$\Delta(\delta_1\textrm{ }\delta_2\textrm{ }\cdots\textrm{ }\delta_{m-1})\rightarrow$ collection/sequence of differences $\delta_j$ for $j=1,2,...,m-1$
\end{landscape}