While this video is giving a basic explanation of Google’s formulae for determining which sites to display (and in what order) when someone performs a search, it does provide a basic explanation of how a general search engine works.
The "deep web" or "invisible web," refers to the vast web content that goes untapped because traditional search engines can't "see" it.
Below are some search engines that access the deep web:
Use Google Scholar search to find journal articles on the net.
Some articles may not be complete, but you may be able to find them in the Library's online databases.
There are many different types of search engines and no one search engine can do everything. Check out these two different sites which give advice on which search engines can meet different needs.
There are added search tools on Google which can help you search more effectively. Check out this Prezi on Google Search tips to find out how to use it more effectively.