drivers side doesnt defog

the drivers side always foggs up and doesnt cleaar when i have the vent pointed at it. the passengers side fogs up at the same time but it defogs easly. WHY would this be? if it is seals can u pleaase tell me where to get some brand new seals.
thx
sry for miss spelling
i got a 91 sunbird le(4.0L OHC)

The passenger side clears up because, simply put your not sitting there.Go to a window in your house,breath on the window.Now hurry up and move over and keep breathing on the window.Which side clears up first?Same concept in your car.

well basicaly I do not have my license yet. I only have my temp permit and my dad would ride with me in pass. side and it would clear up faster then mine. I hade made a thing to rerout the air from the top vent to the side window so i could see out the mirrior. I think it might be the seals because when we are driving i can hear the road outside in the drivers side door.