To search the advertisments see the Job Search page. To find information about a topic, simply type in a few keywords. If you want to do a more refined search, most queries which work with AltaVista will also work here.
Detailed help follows below.
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.