need your help ( rendering )

[ya2]

Hello everybody!
I am trying to render a 3D garment I designed with Marvelous Designer. I am quite satisfied but the rendering is not as realistic as I want (I would like to use the images on an online shop) You will notice on the attached files that there are still imperfections. I don't know if I did something wrong in keyshot or Marvelous. I also tried to smooth the .fbx file (exported from Marvelous ) with Blender.
Please let me know your thoughts about these first renderings and help me to get better results similar to the following one : https://i0.wp.com/cghow.com/wp-content/uploads/2018/10/Marvelous-Designer-Exploration-Part-1.-Raw-cloth-sim-without-Zbrush-6.jpg?ssl=1

Thank you