I'm claiming a search engine can exist without relying on advertising. There are other ways of discovering products and services than advertising. In fact, I'd argue that the amount of things I want I discovered through advertising is minuscule compared to the amount I discovered through direct recommendation, seeking it out myself and professional reviews (I seek out myself).
The only way you would find new products or services is by 20th century word of mouth or search. And search is built on a mountain of ad dollars.
Are you claiming that you don't need Google?