What's wrong with that? If I'm searching for headphones, why would I want to be taken to another search engine that indexes headphones? I want to be see the best prices and be taken directly to the websites that actually sell headphones.
There's nothing inherently wrong with a monopoly. If you think Google is a monopoly, it's only because they provide the best results. Switching to a different search engine is so unbelievably easy, I don't see how you could ever claim Google's monopoly is harmful to consumers.