@MartinSleziak Thanks for bringing up this, on one hand I am looking forward to let more people have the chance to feel its usefulness, but on the other hand I am still working to improve it, I am not quite satisfying about the current model (you cannot get expression if it is a subexpression of the query), I was planing to let more people know it after the new model (what I am working on now) is implemented and ready to use.
But certainly if they feel happy about the current search results quality, I would not mind it is put onto the Help Center. I am also not sure if current online system can work well under a lot of traffic pressure.
