It's not really acting as a search engine, no. You can use Scholar for that, find the DOI, and paste it into sci-hub. Speaking of which, Scholar should really

It's not really acting as a search engine, no. You can use Scholar for that, find the DOI, and paste it into sci-hub. Speaking of which, Scholar should really be showing DOIs on their search results. That is, the DOI should appear as a top-level clickable link from every result entry. I've tried to suggest many things like this to Scholar over the years, but to no avail... Like Google in general. Just a feature request into the void.