How to search for domains that have keywords you like
 

I know that you can do a WhoIs search to find out who owns a domain name and there are plenty of places to search for domain names that are not yet taken. But suppose you want to find out how many domains are already taken that use certain keywords you like... does anyone know of a way to find these? Obviously Google or any search engine can do this but the results may not always provide domain names that have the words you want... more than likely the results will be based on the content of the site and the domain name might be totally different.

As an example, suppose you want to use the word "boob" in your domain name. I'm wondering if there is someplace you could go to enter the word "boob" and find all of the domain names that have already been purchased that include the word "boob". It would be sort of like a WhoIs search but for existing domain names instead of the owner records.

The purpose of doing this would be to get ideas for alternate domain names and also to see how many other domains are already using your keyword.