Using the following on Google and Yahoo filters results by site, but not in Bing:
Is there a Bing equivalent?
Bing supports the use of the site: filter in the search bar. I just performed a test using Bing and doing a search for a government department in Australia to filter just on departments website for the keyword earthquake.
The search string used was
site:ses.vic.gov.au earthquake and the results returned was as expected only pages from that domain with the keyword of earthquake as can be seen from this link http://www.bing.com/search?q=site%3Ases.vic.gov.au+earthquake&go=Submit&qs=n&form=QBRE&pq=site%3Ases.vic.gov.au+earthquake&sc=8-28&sp=-1&sk=&cvid=F9AC5EDF8C494F6FA247CF33415DC2CF.