@jeanralphio: It's not bad. The few tips I can give you is practice your anatomy a little more, what works best for me is referencing photos. Body builders both female and male will give you a good idea of muscle placement and proportions. One other thing that I noticed on your drawing is that you may be smudging the shading, This will give your pieces a flat look. Don't be afraid to go dark with your shading it will add some dimension. Hope this helps keep up the good work.