What Causes Smelly Discharge From The Vagina?

My vagina have a certain smell to it, it is not bad or good, but it still smells, and I have tried everything, I change my underwear more than 3 times, I eat fruit, and I wash it with water every time I use the rest room, ( sorry for tmi ) but idk what to do, I never had intercourse, but I had an oral sex, please help,