I Have Bad Breath. I Have Healthy Teeth No Decay.

I have bad breath. I have healthy teeth no decay. My gums are fine. I brush my teeth 3 times a day, I brush my tongue too and I use mouthwash with zinc chloride and cetylpyridinium chloride. I used saline solution with eucalyptus oil to clean my nosr but my breath still smells very bad. Even if I close my mouth the smell comes out of my nose. what should I do? Please I need help