Why is it when my girlfriend gets wet and I touch her, her liquid smells bad? Could it be she needs to douche more often?
If she's paying attention to proper vulvar hygiene -- washing the vulva with warm water daily, and a mild soap if preferred -- and a realistic expectation of human secretions is still rendering her vaginal discharge unpleasant, she should see a doctor. Vaginal fluids should never smell anything close to unpleasant or foul, and paired with any abnormal color or texture, ought to be suspected symptoms of infection. If she has had any contact with sexually transmitted infections, this is all the more important.
Douching will only make the problem worse, or better yet, create one when there wasn't one in the first place. This is because the vagina is lined with good bacterial cultures (the same ones that line our intestines and aid in digestion and immunity) and a pretty exact pH that helps keep invaders at bay. Douches wash out the natural bacteria, alter the vaginal pH, and on top of that, add potentially irritating, unnecessary fragrance. Combined, this is the perfect way for a female to wind up with a yeast or bacterial infection. The latter is diagnosed with a whiff test; a smell similar to rotting fish helps the clinician in obtaining a diagnosis of BV. "Spring freshness", indeed!
More likely than not, it'll simply take an attitude adjustment and simple hygienic steps to a better aroma. Check out these articles and resources for more on that: