is:unread.All the unread mails will be listed..wow..nice one isnt ?
See below options too .
Keyword what it will do ?
from:abc --- get all mails from abc
to:abc --- get all mails send to abc
is:read --- get all read mails
is:unread --- get all unread mails
is:starred --- all starred mails
in:inbox --- mails in inbox
in:trash --- mails in trash
in:spam --- mails marked as spam
Many options are there.. Get the entire list from See here