The point of sci-hub is that it fetches specific articles for you, not to be a search engine. Find an article you want - for example, the PolderCast paper[0] - then enter a link or the DOI for that article, and it'll find the paper most of the time.
Unfortunately not, I tend to find something close to what I want via Google and then find papers that it references, and papers that reference it. Review articles are useful, as are benchmark comparisons that you find in some papers.
[0] https://dl.acm.org/citation.cfm?id=2442644