Good quick figures. Now move up to longer timed drawings. To help you. You need to study human anatomy, both muscle structure & bone structure. The study will help you know what you are drawing. You can find a lot of information on the subject on the internet. Recommend you make drawings of what you find enough so that you know what is what. Drawing nude figures will help you in drawing clothed figures. I would recommend a simple stick figure so you can more easily get the dynamics correct. Once you are happy with this drawing, you can expand the figure to more realistic forms.
Remember: practice makes better. That is what you are after - improvement.
Love all those gestures, yotastrejos, greatest job on those yet. Greatest job on the line quality of those gestures. Greatest job in all of them.
I've got one small suggestion: What is your goal for today? The reason why I asked is because, what is your current goal for tonight?? If you really want to strengthen your movement and action-packed quality into your work, pick up a copy of Vols. 1 and 2 of the Walt Stantchfield Books on Animation. They have almost everything that a non-animation school and animation school student is looking for to give all their drawings their range of expression and storytelling ability.
For now i would like to learn some about the movement of the human body and some anatomy. But I dont have a clear goal. I have different interests like comics and caricatures so definitely being expressive is something worth learning in my case. Ill going to check out your recommendations!