You can help yourself immediately here....to some degree...

Your fan is positioned in such a manner that it is going to suck in hot and blow hot air out the door. You are not getting IN any fresh air.

You need to add a fan and have it blow INTO the room at a level lower that the one you have blowing OUT of the room.

That will create immediate improvements in air flow.

So you need two fans.

One low in...one higher out. That might help keep a buffer for the top layer of heat until you can exhaust out of the room.

Remember though, to exhaust OUT you must also exhaust IN.

HAPPY EXHAUSTING