[X-plor] ligand density

[hothot c]

Dear all:
 I'm refining a protein complexed with its inhibitor.However, the ligand 
density is only visible if I refine the structure and calculate the density 
at the range of 20-2.37 angstrom but not visible in the range of 10-2.37 
angstrom.
Please advise.
Rong