No, they don't but I know what you are referring to.

Most of the time I get the result:

  No results found for [phrase]
  Results for [phrase] (without quotes)

..but the thing is that I know websites containing [phrase] exist. Often many of them and they aren't "dark web" either. Google used to be able to find them but no longer is.

This gets more confusing because sometimes it does work. Namely if you look for phrases which are popular search queries e.g. if you search for..

  "hit me baby one more time"

..it will work amazingly well. But for other phrases it won't work at all and you will get the no results reply instead. It used to work for all phrases independent of their search popularity.

But yes, my original post was wrong. It does work for a lot of phrases.. but not for others.

I guess Google's engine dynamically optimizes things, and only indexes often searched phrases.

EDIT: Okay, this assumption was wrong too. I did some experiments to confirm my theory and the results showed that it is wrong..