You know the saying "walk before you run"? That's the trick really. I think your hair looks pretty nice, and the nose looks pretty good in the first one, but before you start drawing a face, start with the basics: break it down into individual parts and shapes and where the features sit on a face. I know it's tough and you might get impatient and want to jump straight to a finished drawing, but...well, basically don't do this: http://www.forimpact.org/wp-content/uploads/2014/01/HowToDrawOwl.jpg
Now some people will say to not jump straight into the manga/anime style, and a lot of people saying that are better artists than me so it's not necessarily bad advice, but if you're just doing it for fun, knock yourself out. But regardless of the style you adopt, even in practice sketches, if you're looking to improve, it's important to start with the basics. Before you start adding details, know/sketch/outline where on the face each feature is supposed to be.
This whole video, good stuff here
And for the love of all that is holy, don't pick up a "how to draw manga" book. They're typically riddled with terrible advice and guides. Unfortunately good advice is hard to find because everyone has their own method of drawing and their own way of learning, so the important thing is to find what works for you.