Removes "stop" or "delete" words that google removes from search strings. Ordinarily have no search significance. I used this to remove the words in my own web search application. Take out the ?: for grouping. 
\b(?:a(?:[nst]|re|nd)?|b[ey]|f(?:or|rom)|i[nst]?|o[fnr]|t(?:o|hat|he|his)|w(?:as|h(?:at|en|ere|ich|o)|i(?:th|ll)))\b