Perhaps you should try some spelling variations:
"coder coding efficient obstacle problem" » "coder coding efficient stable problem" (Expand search), "coder coding efficient state problem" (Expand search), "coder coding efficient instance problem" (Expand search), "coder coding efficiency obstacle problem" (Expand search), "coder using efficient obstacle problem" (Expand search), "coder crowding coefficient obstacle problem" (Expand search), "modern coding efficient obstacle problem" (Expand search), "color coding efficient obstacle problem" (Expand search), "odor coding efficient obstacle 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), "rpa python 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 coding efficient obstacle problem") OR ("api python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coding efficient obstacle problem\") OR (\"api python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coding efficient obstacle problem ) OR ( api python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coding efficient obstacle problem") OR ("api python python python programming"))*.