My husband have been having something like flems in his throat and he has seen several e.n.t specialist but it looks like there is no improvement.

Phelgm in throat: This phelgm in throat may be related to allergic rhinitis and post nasal drip since he has already seen ENT specialist it does not seem to be a structural problem like deviated septum, or polyps. Use saline nasal lavage two or three times a day, and the drainage will decrease. Antihistamine nasal spray and inhaled nasal sprays may be tried. Please see your primary physician.

Lungs?: The phlegm may be coming from the lungs. This could be due to asthma, chronic bronchitis etc. He may need to see a lung specialist.