Bad breath reasons can be any decayed tooth or tartar on your teeth .... cAn be either any other tooth related or systemic problems like acidity etc.
Next Steps
Visit your nearest dentist and get your check up done and find out the cause of bad breath and get it treated
Health Tips
helpful tips can be
you can use any mouth rinse or warm saline rinses
plus for extra saliva you can use duestom easily available in market massage it twice a day all over mouth