Only real solution I know of is getting your data (it's JSON iirc) and using some parser to search through it.
> Graph Search will now let some members uncover status updates, photo captions, check-ins, and comments.
Seems it's still not available for everyone, at least it doesn't work for me. Good thing it's finally coming though.
[0] http://www.cnet.com/news/facebook-expands-graph-search-to-le...!