Some key concepts of searching apply to ALL databases .
All databases do the same thing.
The quality of your results is based on the quality of your search terms and your understanding of how to communicate with the system. Indexes are produced by many different companies. They compile the citations into an index, using electronic typesetting methods. This results in electronic tapes that contain the indexing information. Each vendor has a different method of communicating with its system, that is, a different way to tell the system to search, truncate a word, limit a search and print results.