We've talked about what words to use... let's talk about what words not to use when constructing search statements.
The ten most common words in the English language are:
Remember the tip from Chapter 1? Most keywords are nouns. So except for "and", which as we know has its own special meaning when it comes to computer searching, you will want to avoid using these common words in your searches. Maybe not coincidentally, none of them are nouns.
So, if you want to know about:
AIDS in Africa
AIDS and Africa
Effects of radioactivity
Effects and radioactivity