GDSearch (Google Desktip Search) is an alternative File search plug-in for Eclipse. Instead of using the default (and kind-of slow) File search capabilities, this plug-in uses the Google Desktop Search Engine instead.
The search can be started from either the Search menu or the Google Desktop Search Toolbar Action:
It can of course also be reached by using Ctrl-H like other Searches and switch to the "Google Desktop" tab. This tab lets you enter in the search term and which context to search for it. You can also speed up the search by selecting just an extension to search for (like java, which is the default extension).
For more detail: http://eclipse.moelleryoung.com/gdsearch/
Recommend the tutorial