Perhaps you should try some spelling variations:
"coder coder using frequency spectrum" » "coder coder single frequency spectrum" (Expand search), "coder coder feeding frequency spectrum" (Expand search), "coder coder grazing frequency spectrum" (Expand search), "coder decoder using frequency spectrum" (Expand search), "code code using frequency spectrum" (Expand search), "decoder codec using frequency spectrum" (Expand search), "coder coders using frequency spectrum" (Expand search), "coder cover using frequency spectrum" (Expand search), "coder code using frequency spectrum" (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.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder using frequency spectrum\") OR (\"api python python python programming\"))~".
• Removing quotes may allow a broader search: (( coder coder using frequency spectrum ) OR ( api python python python programming ))~.
• Adding a wildcard symbol may retrieve word variants: (("coder coder using frequency spectrum") OR ("api python python python programming"))*.