what else can we do? what do we need to fix it?

I just brought a 1998 chevy cavalier with 2.2 enige. When brought the car the guy told me he took out the daytime running light. Since I brought the car, the low beam headlight is not come on. we check the fus. we change the light bulb. we if check the wire and there is no jucie going to the low beam wire.