Suggest Treatment For Vaginal Discharge

hi, i have had vaginal discharge for a long time and i have tried everything, from thrush pessaries to bv tablets and bv liquid injection, i have cut out bubble baths and using soap near that area, different underwear and still no result. What is this? How can i treat it? It's really getting me down, i have been tested for sti's stds, i am all clear. I hope you can help. Thankyou, stressed.