This results in questions from users every week. At first, users get really excited about the webclient that they can search without specifying the field. But users tend to search on names and descriptions a lot, and yes those are look-up flowfields if it's data from a linked table.
So now we do a lot of explaining what flowfields are and that you can't search on them, but that they can try to filter with something like @*name* on the flowfield. And then they get disappointed.