Lokalize

Lokalize is localization tool for KDE 4. It is a replacement for KBabel which is now discontinued.

Search in files

TM now keeps track of where each translation pair came from. So when you want to search for string in the files on disk, you just drag the directory with those files onto translation memory tab (F7) to update TM, wait a minute or two, then type your string into right field of Translation Memory tab, then press Enter.

Then you click on one of results and this opens appropriate file, on appropriate entry. When you want to do another search during the same day, you skip updating step and just type what you're searching for. You can filter TM search results by filename using the field left side of the F7 panel (Filemask).