Perhaps you should try some spelling variations:
"coder precoder discrete coverage problem" » "coder order discrete coverage problem" (Expand search), "coder precoder scheme coverage problem" (Expand search), "coder predador discreto coverage problem" (Expand search), "coder precoder discrete covering problem" (Expand search), "coder precoder discrete coverage from" (Expand search), "coder decoder discrete coverage problem" (Expand search)
"api python python python programming" » "api pythons python python programming" (Expand search), "api piton python python programming" (Expand search), "api pitons python 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 precoder discrete coverage problem") OR ("api python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder precoder discrete coverage problem\") OR (\"api python python python programming\"))".
• Removing quotes may allow a broader search: (( coder precoder discrete coverage problem ) OR ( api python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder precoder discrete coverage problem") OR ("api python python python programming"))*.