best way to handle a email subscription and narrow down the emails.

We are using SCOM 2012 SP1 and have everything updated to UR5.

We have 2 groups defined.   Machines with names starting with Corp- and Prod-.     We have a subscription to notify on errors with this group.   We get many different alerts that are not necessarily important with this subscription so we want to  narrow down the focus.

We would like to use these two groups but only send out notifications when certain types of events happen like

CPU utilization is too high or   logical disk space on C: drive is low (dont care as much about D: or E: etc).

Is there a way to do this with criteria set to specific rules or monitors?

Thanks Lance