A simple string of terms like sas excel spss will find documents containing one or more of the terms. Better matches, preferably containing more than one of the terms, will be listed first. If you search for TeX , you'll get only documents that include that word with just that capitalization. If you search for tex , you'll get any document containing that term. Use this if the word you are searching for could have different endings.
Wild cards work even within phrases.
Placing punctuation or special characters between each word, with no spaces between the characters and the words, is also a way to indicate a phrase. Although almost every line has been re-written, this indexing search engine is based on the Xavatoria Search Engine by Fluid Dynamics . This page maintained by Gordon Smyth , Department of Mathematics, University of Queensland.