The most common saying in golf is "keep your head down." The question is, are you actually picking your head up? When you hit a thin shot that dribbles along the ground, it would seem that a player must have picked their head up. My experience is that most player's don't pick their head up at all, what they do is pull their arms and hands up toward their body causing the club to hit the ball low on the clubface producing a skull shot. To fix the problem, hit balls focusing on brushing grass ahead of the ball and going to a three quarter, fully extended finish. This will help keep your arms extended producing more consistency and power.