Perhaps you should try some spelling variations:
"coder coder plot allocation problem" » "coder coder plot location problem" (Expand search), "coder coder slot allocation problem" (Expand search), "coder coder profit allocation problem" (Expand search), "coder coder point allocation problem" (Expand search), "coder decoder plot allocation problem" (Expand search), "code code plot allocation problem" (Expand search), "decoder codec plot allocation 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 plot allocation problem") OR ("on python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder plot allocation problem\") OR (\"on python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coder plot allocation problem ) OR ( on python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coder plot allocation problem") OR ("on python python python programming"))*.