Hi, Genie - I usually look for exact phrases or distinctive words that I know are likely to be only in the type of document I'm looking for - same thing I do when I'm searching Mudcat. My favorite search engines are Google and Hotbot. Most people just put words in the search box of these engines, but both have "advanced" search links that can help you narrow your search.
With Google, try searching for "two phrases", and be sure that "each is in quotes". I have to say I haven't bothered learning Boolean terms like NOT and NEAR and AND - but I look up instructions and use them when I need to (or use the "Advanced Search" option).
Hope that helps.
-Joe Offer-