Air flow from vents

It seems the air flow from the vents is not real stong. Is there anyway to increase the pressure of the air flow?

Thanks.

Depending on what year truck you have, there is an "in cab" filter on the new body style trucks (99+) It is under the dash on the passenger side. I've seen them stop up and no air will blow through the vents. I used to have the part # for a replacement. If you need it, I can find it again.