While the Registry Editor does have search capability, it is rudimentary. A better solution is using REGEDIT.EXE (the Win95 editor) for performing searches using the edit/find menu (do not make changes with this editor). Better yet, get a good shareware package such as Registry Search and Replace.
Once in a while, none of the search tools
will find your Key/Value/Data! The best way to combat this is
to highlight the Key (or Hive) you wish to search (in Regedt32)
and from the Registry menu select Save Subtree As ...
Browse to the directory you want and save it as YourPreferedName.txt. Now you can search in any text editor or Wordpad.