The reason it doesn't look like the sketch is because you must understand what you are tracing and why you did something in the sketch for example the hair: in the sketch the tuffs of hair coming off the side looked to be coming from the side of her head , but when you sketched it you made it look 2d and made it look flat , or the hair a top the head it went from the starting of the front bangs covering up the starting of the back of the head hair of the character to everything being connected and making it look again 2d , also notice the feathers next to her thigh in the sketch how the feathers curl and seem more 3d and now look at the trace how they look strait and flat and 2d , all of these things come together to give your drawing a flat looking appearance in places , I recommend working on perspective drawing or taking 10 min breaks while drawing so you come back refreshed so you can notice your mistakes