Metacrawler

http://www.metacrawler.com/

metacrawler is a metasearch engine that receives results from the most used searchers like Google, Yahoo!, Bing (formerly Live Search), Ask.com, About.com,MIVA, LookSmart it doesn't only search for websites but for images, videos, and white and yellow pages, and that is what makes metacrawler better for looking for specific and uncommon information than any of the searchers mentioned before as long as metacrawler doesn't limit the results to one of them, it builds a new list based on our needs and according to the popularity  of the site proposed and its accuracy to the searched words.
Anyway, we highly recommend to use boolean operators to enhance the accuracy of the search.
just a reminder of them.

Use	To
AND	Narrow search and retrieve records containing all of the words it separates.
OR	Broaden search and retrieve records containing any of the words it separates. The | can be used instead of 'or' (e.g., 'mouse | mice | rat' is equivalent to 'mouse or mice or rat').
NOT	Narrow search and retrieve records that do not contain the term following it.
( )	Group words or phrases when combining Boolean phrases and to show the order in which relationships should be considered: e.g., '(mouse or mice) and (gene or pseudogene)