I am using a dock-design protocol to design a binding pocket to bind a ligand. I know where parts of the ligand should bind (orinetations and the position in protein) but the other parts can be flexible. Right now after the dock and design protocol, most of my outcomes change the whole position of ligand and don't keep that part fixed. Is there a way to tell the program to keep parts of the ligand fixed? or a way to generate conformers for only parts of the ligand?