I've been happily using @deanishe's workflow above to search within the Calibre app using Alfred 4. But I've just installed Alfred 5, and the workflow doesn't seem to work there. It brings Calibre to the front but doesn't search - and doesn't highlight the search-bar in Calibre, so I think the script must be failing at the point where it uses Cmd-F to enter the search-bar. I've checked all the variables and they are the same in both version of Alfred.
I've had a look at a couple of other workflows that have been posted but can't get any of them to work in Alfred 5 either.
Would anyone with more expertise than me be willing to try to fix this?