2-story bungalow with poor heat flow on the 2nd floor and basement... is this due to air duct blockage?

DO you have an air exchanger in the area's of poor air flow. Usually if the house does not have a way for the air to get back to the A/C unit/furnace, the flow will be very low. Even having tight sealing doors will cause a problem. Is there enough clearance between the floor and door for good air flow? DO door slam when you open an exterior door. IF so then you need a bigger gap under your doors. These are are few things you can check and change to get better airflow.