Please use \mathbf instead of \bm. So for example write:

$\mathbf{O(\log n)} + \mathbf{O(\lambda,\,\epsilon)}$

If your document already has a lot of \bm commands you can include this snippet in your header.tex:

\usepackage{bm}
\renewcommand{\bm}{\mathbf}

Published on: 01 / 06 / 2019