I am getting blood from the mouth
sometimes. i found that it is from below and sides of the tongue and not from the throat or teeth.
nowadays it is becoming more frequent
Bleeding from the tongue is not a good sign if that is the exact location of bleeding as per your description.
If the bleeding is actually from the gums it can be corrected by cleaning of the teeth. You should visit a dentist as soon as possible so that the exact cause of this bleeding can be identified and the right treatment can be instituted accordingly.
Alternatively you can post clinical pictures of the affected areas on Practo for an online consultation with a specialist.