Google search showing up results that don't contain the search terms

http://www.google.com/search?num=100&start=0&q=%28%22religare%22%29+%28%22r开发者_JAVA百科eligare+art%22+OR+%22religare+arts%22+OR+%22art+initiative%22+OR+%22arts+initiative%22+OR+%22business+of+art%22+OR+%22arts-i%22%29&lr=lang_en&tbs=vid:1,sbd:1,qdr:m,lr:lang_1en

Consider the fourth result in this case. It doesn't have any of the search terms. I am working on an ROR application that depends on this kind of searches, as we are scraping data from the Google search results. This has me totally flummoxed.

Google uses words from pages linking to that page as well as text in the URL and various other sources in its index. It also does stemming on query words and will search for synonyms as well.

See also: http://www.googleguide.com/google_works.html