You can use booster fans in those rooms/open doors so the heat can travel freely up the stairs. You can also use baseboard heaters and space heaters; make sure the walls are insulated and sealed so your heat won't be wasted/escape through leaks/cracks. Put in extra duct work into those rooms/more vents. Insulate the floors.
Partially close the vents to rooms that are getting enough heat. _____ Forced air will take the path of least resistance. If you want it to take a particular path, you need to put more resistance in the paths you don't want it to take. Ultimately, there is only so much flow volume, so you need to decide how you want to allocate it. As a rule, it will not be possible to heat every room quickly. However, it is usually possible to heat every room adequately--provided that your heating plant is properly sized.
Besides installing ceiling fans in each room, open a window in the farthest rooms to draw the heat to them, and close partially the hottest rooms vents.
