Why does your central air conditioner not blow cold air if you checked the unit outside and its running Also checked the breakers The force of air coming through vents isn't strong and the air is warm?

There are many reasons why it does not work: it may have lost all its refrigerant because of a leak in the system; its compressor pump may have stopped working; etc...

If you cannot see anything obviously "set wrong" on the controls of the ac unit, the best advice anyone should give you is to call a licensed Heating, Ventilation and Air Conditioning (HVAC) technician to advise you and/or fix it for you. For personal safety reasons only technicians who are licensed to work on HVAC (Heating, Ventilation and Air Conditioning) should do this kind of work because they have the right test equipment and tools and have been trained in how to do this work safely.