They have a new artificial intelligence bot called "Rankbrain" that uses machine learning to match up results to search queries Basically if someone, anyone, in the world has searched for something, however unusual, and then selected a certain result, rankbrain remembers it, and when the search is done again by someone else, it produces what the original searcher clicked on. Of course if you are unhappy with the result and backspace into the results and click on something else, it remembers that too and refines it's results.
The machine learning aspect is what makes it so powerful. The old algorithms were "pre-set" in that they used an assumed criteria to decide what results to show. But RankBrain is actually learning in real time what people like.
Wow. That might be it... I am still wondering about this one time if it was user error because I remember typing one letter 'a' and I got the entire search result! So I was second guessing myself about maybe having typed it in before and not remembering. I think I typed 'a' and it suggested the entire search string I was thinking of: 'adjective that starts with e'.... so the question is did someone in this forum type that in a search from Steemit for this post: S.T.E.E.M.? It would be great if someone could recreate it to be sure. I'm still leaning towards user error. lol. Type in 'a' on the search bar. That would still be pretty wild.