Great be back but purchase emails?

[soMe_RandoM92]

So um I been going through my files find my cd keys again, I had them somewhere in my Google account but That blown up to massive amount emails over the years and I cant seem find file that had all my keys. So, quick help with what does purchase email subject look like so i can just use search function (Hopefully i can), find them quickly, not that urgent but, its haha. Quite few, like 3 keys hidden away.

[Zair]

If it's a gmail account, searching for 'AI War' or 'Arcen' might turn up something. Their searching covers both subject lines and the contents of mails themselves.