Well, I have no idea how to translate the non-english bits, but this bit:
Code:
You must specify a search expression in the "Search for" field
is very telling.
Basically, calibre was updated for some reason or another, to be more robust probably (I cannot remember), and now if you want to search via mass S&R, you will need to have some form of search, even just a dot is enough.
I think it may have had something to do with the move to the new database, there was also this:
https://github.com/kovidgoyal/calibr...d6fd77ed5ad3be
Which fixed this bug report:
https://bugs.launchpad.net/calibre/+bug/1282357