Ever wondered which search queries drive the most revenue for Google? It turns out that iPhone, insurance and cheap flight queries drove the most revenue for Google in the U.S., at least for one week in September 2018. The list of search terms appeared on a heavily redacted slide that was included in a PDF released this week as a trial exhibit during the ongoing U.S. vs. Google antitrust trial. But we’ve never known which search terms were the most lucrative for Google because Google has never before revealed this information. The 20 most profitable Google searches.