Searches in MacOS

I have a friend who uses MacOS and when he does a search he gets double quotes. For example if we do the search: authors:”/“ , in order to see if there is any author name that contains a forward slash, Calibre does not do the search…
I have suggested that you put space between: and the quotes like this authors: ” / “ In 5.42 and 5.43 it doesn't work. If it works in 5.40

Attached Thumbnails