Deleting emails from a search folder is very slow

Re: eMClient 7.2.34711.0; Windows 10; IMAP

I have several search folders for emails. A typical one just filters for unread emails received after a certain date, but others don’t involve dates. Deleting emails from these folders can take 5-15 seconds just for one email. It helps to select a number of emails and delete them all at the same time but the deletion still takes 5-15 seconds.
It really isn’t comparing to other programs in speed.