I believe that an earlier version of Dolphin enabled one to search for a file by date. This facility seems to have gone. If I wanted to to search for a Libre Office writer file modified last August,say, but had completely forgotten the file's name, I would enter *odt and a dialog box would offer me the opportunity to narrow the parameters to files modified between 1/8 and 31/8, and return a few files. Now the search will return hundreds of files. Admittedly it is quick to sort by date, but the list takes much longer to create.