they make so much money from ads, in part, because they are trusted by customers to be clever enough to magically put the right ads in front of the right people, and enough right people. Their other products may not make a lot directly, but boy are they strategically beneficial. Search is absolutely key, obviously, but youtube is the second biggest search engine. Gmail puts ads infront of people but also aids the AI behind context aware smarts.Everything they do can be said to help those ads become more effective, larger in volume, more trusted and seen by more people. Their may be some obscure contradictions, but name a few. I bet we can see how they help their ad revenue.