Welcome fellow settlers,
Although I only played this game for a short while, I noticed that there is no real way of filtering individual mails.
Maybe there is a way to mark certain mails that you find important.
I sometimes search some time before I get to the mail I want, and with all these buffs you get it might get overwhelming.
So what I would suggest is a way to mark those important mails with a star (like most other mail services do) so it's easy to find back the mails u need.
Thanks in advance, wsids