Zoom in / Zoom out symbol

I use instead fontawesome5 package of Marcel Kruger of the June 7, 2019 (the lens grip should be different from fontawesome with the command \reflectbox to obtain the very similar image of the user @Sr. Schneider.

\documentclass[a4paper,12pt]{article}
\usepackage{fontawesome5}
\usepackage{graphicx}
\newcommand{\faSearchPluss}{\reflectbox{\faSearchPlus}}
\newcommand{\faSearchMinuss}{\reflectbox{\faSearchMinus}}
\begin{document}
\faSearchPluss, \faSearchMinuss
\end{document}

Finally found it in the fontawesome package: \faSearchPlus and \faSearchMinus.

You can use the tikz machinery.

\documentclass[border=3pt]{standalone}

\usepackage{tikz}
    \usetikzlibrary{calc}

\begin{document}
\begin{tikzpicture}
% \node[draw,line width=2pt,circle,inner sep=2pt] (A) at (0,0) {$-$};
\node[draw,line width=2pt,circle,inner sep=2pt] (A) at (0,0) {$+$};
\draw[line width=2pt] ($(A.225)+(.5\pgflinewidth,.5\pgflinewidth)$) -- ++(-1em,-1em);
\end{tikzpicture}
\end{document}