Perhaps you should try some spelling variations:
"coder coder operation planning problem" » "coder coder conservation planning problem" (Expand search), "coder coder operation packing problem" (Expand search), "coder coder operation planning process" (Expand search), "coder condor operation planning problem" (Expand search), "coder mode operation planning problem" (Expand search), "coder cyber operation planning problem" (Expand search), "coder decoder operation planning problem" (Expand search), "code code operation planning problem" (Expand search), "decoder codec operation planning problem" (Expand search)
"on python python python programming" » "on pythons python python programming" (Expand search), "on piton python python programming" (Expand search), "on pitons python python programming" (Expand search), "in python pythin python programming" (Expand search), "of python pythof python programming" (Expand search), "_ python pyth_ python programming" (Expand search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("coder coder operation planning problem") OR ("on python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder operation planning problem\") OR (\"on python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coder operation planning problem ) OR ( on python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coder operation planning problem") OR ("on python python python programming"))*.