This is hard to answer without seeing your current title; I have wondered this about my own titles, but I tried to make them the same search terms that my prospective callers would be entering. This unfortunately makes them boring, but I do not think this is an opportunity for intrigue.

I suppose you could consider a clickbait type strategy (e.g. "My Top 7 Secrets to Doubling Revenues for a Service Business"), but that might seem hokey.

Then again … it might work. Perhaps try it out for 3 months, and then compare that period to the prior one?