Perhaps you should try some spelling variations:
cdc diffraction » ray diffraction (Expand search), and diffraction (Expand search), of diffraction (Expand search)
diffraction x » diffraction xrd (Expand search), diffraction drx (Expand search), diffraction of (Expand search)
python python » pythons python (Expand search), piton python (Expand search), pitons python (Expand search)
x decrease » _ decrease (Expand search), l decrease (Expand search), α decrease (Expand search)
code cdc » code cpc (Expand search), code ctn (Expand search)

You may be able to get more results by adjusting your search query.

• Removing quotes may allow a broader search: (( code cdc diffraction x decrease ) OR ( _ python python python programming ))~.