I agree with GRose, it's always there you might not see it all the time but it's there. You can't get rid of it, it's normal for all women. Try searching vaginal discharge on google and you might find a more detailed explanation.
It is most likely just your normal discharge as long as there is no foul odor, weird color and no itching with it. All women have discharge, it is the body's way of cleansing itself.