Mercurius

Mercurius is an internet search application for Windows that will help you to narrow search results by suggesting keywords and phrases you could use in your next iteration.

If you have ever been daunted by the number of results returned by search engines, or found it difficult to think of the keywords to use to find something, then why not try Mercurius?
With Mercurius, you perform a preliminary search using your 'best guess' keywords, and then use any keywords suggested by Mercurius to make the search more specific. You can iterate the search as many times as necessary, using more specific keywords each time, narrowing it down until you find what you want.