bookmarking ability of PDF::Reuse
POD is misleading, this simply jumps to target page, to same coordinates and zoom as on currently active page. I doubt it's what's expected if user wants to go to particular line of text. So, expect at least to read the manuals and patch the source.
+ What kind of "specific string"? E.g. wkhtmltopdf adds bookmarks to what were HTML headers, and I think any decent converter has similar abilities. That said, extracting text (either plain text or XML with coordinates and attributes) from PDF page by page to find page number with required string is obvious and perhaps you are already testing this solution...
Edit: PDF::API2::Outline also adds bookmarks.
