I remember services available 5+ years ago that would help you with this kind of thing (scanning through email archives by sender), but the ones I remember have all morphed into "tame your inbox" apps, which doesn't solve the same problem.
I remember services available 5+ years ago that would help you with this kind of thing (scanning through email archives by sender), but the ones I remember have all morphed into "tame your inbox" apps, which doesn't solve the same problem.