With ranked relevance searching you may get hits that contain only one of your search terms. The best advice here is to use as many terms as you can think of to describe the concept you are searching. There are other sites which are large subject directories of pages that the providers find or are submitted to them. The search engines at these sites only search the web pages that are listed in the directory. Most of the search services also provide subject directories.
Some sites provide the ability to search many indexes and other internet resources from one page.
There are many CUSI sites around the world. Each is set up slightly differently. The common factors are that you can choose which resources you want to search, they are sorted by resource type and you do not need to re-enter your search as you move from resource to resource. Savvy Search SUSI - configurable in that you can specify type of information, number of results and type of query.