Perhaps you should try some spelling variations:
"coder coder standing wave problem" » "coder coder standing waves problem" (Expand search), "coder coder standing wave problems" (Expand search), "coder coder standing waste problem" (Expand search), "coder coder standing paves problem" (Expand search), "coder decoder standing wave problem" (Expand search), "code code standing wave problem" (Expand search), "decoder codec standing wave 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), "manim 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 coder standing wave problem") OR ("api python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder standing wave problem\") OR (\"api python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coder standing wave problem ) OR ( api python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coder standing wave problem") OR ("api python python python programming"))*.