\documentclass[12pt]{article}
\usepackage{fontspec}
\usepackage[unicode]{hyperref}
\usepackage{accsupp}

\newcommand{\pdfwrap}[1]{{\fontspec[Script=Latin]{DejaVu Serif}\BeginAccSupp{method=pdfstringdef,unicode,ActualText=#1}#1\EndAccSupp{}}}

\begin{document}

a\pdfwrap{b}c\pdfwrap{d}e\pdfwrap{f}g\pdfwrap{h}

This \pdfwrap{word} must appear in the text.

\end{document}