It's a slow slog, the way I force a title when nothing is coming to me. I start with a list of key words. So if my imaginary novel is about, say, a woman who bartends in the tasting room of a craft brewery, where she meets The One--or is he?--I'd write brew, brewery, beer, ale, lager, bar, bartender, keg, hops, bitters, drunk, saloon, tavern, and similar words, as many as I can think of.
Then I get out books of quotations, indexes of poetry, nursery rhymes, Shakespeare, the Bible, mythology, and similar reference works, both print books and online. Whole lot of tabs open!
Then I look up my words. Most of what I find won't produce a title, of course. Some of it is also protected by copyright or trademark.
Next I copy the complete quotation of anything with title potential. Usually I end up with two pages of quotes, and somewhere on those pages lies the title. I just have to find it.