As far as I understood , ( my spain is lousy ) Kalaita is right There is NO difference between "woher kommst du?" and "wo kommst du her? [ I think , in my opinion "wo kommst du her?" "wo gehst du hin? " is a little more used in general speaking "woher kommst du? " "wohin gehst du? " sound a little little little bit more formal , to me ...this could also be ment in a Philosophical sense ... ] Its really hard to find a difference between those sentence You can use both in any situation , you will never do wrong You can use as you like without any probleme

Las dos son correctísimas, simplemente el "Wo kommst du her" es una forma más coloquial que la primera, pero repito, puedes utilizar cualquiera de las dos formas.

Es gibt keinen Entershied zwischen den zwei Saetzen!!!!!!!!!!!