Recovering Emails deleted

Desperately need some help.

My wife has deleted emails from her Mac a few months ago. Is there anyway that she can recover these emails?

If so, as I am an absolute idiot with computers, could you guide me if I need to get a programme or what I need to do.

Appreciate any help.

Thanks

Darren

What email program does she use?

Does she use Time Machine to backup her Mac?

And one dumb question--Did she look in the Deleted Items folder in whatever email program she's using?