My Primary Doctor Is A Pulmonary Specialist. Im Not Getting

my primary doctor is a pulmonary specialist. im not getting good results from his diagnosis. ive heard of dr. frank de maio. he is 84 years old. just how competent is he. who would be the most noted for breathing disorders. I have a constant cough. the prelimaries show nothing in the x rays. im on a nasal spray and an inhaler. not really helping too much.