ADD THIS BEFORE \begin{document}
% add changemargin environments
\newenvironment{changemargin}[2]{%
\begin{list}{}{%
\setlength{\topsep}{0pt}%
\setlength{\leftmargin}{#1}%
\setlength{\rightmargin}{#2}%
\setlength{\listparindent}{\parindent}%
%\setlength{\itemindent}{\parindent}%
\setlength{\parsep}{\parskip}%
}%
\item[]}
{\end{list}}
ADD THIS WHERE YOU WANTED YOUR DESCRIPTION
\begin{changemargin}{100pt}{0pt}
\begin{description}
\item[myDesc] test
\item[myDesc2] test2
\end{description}
\end{changemargin}