I remember there was a fancier term for these common words, that search engines ignore.
They're called stop words:
In computing, stop words are words which are filtered out before or after processing of natural language data (text). Though stop words usually refer to the most common words in a language, there is no single universal list of stop words used by all natural language processing tools, and indeed not all tools even use such a list. Some tools specifically avoid removing these stop words to support phrase search.