Perhaps you should try some spelling variations:
"coder decoder pid control problems" » "coder decoder pid control program" (Expand search), "encoder decoder pid control problems" (Expand search), "video decoder pid control problems" (Expand search), "coder decoder in control problems" (Expand search), "coder encoders pid control problems" (Expand search), "coder decoder and control problems" (Expand search), "coder decoder pid controller problems" (Expand search), "coder decoder weed control problems" (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 decoder pid control problems") OR ("api python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder decoder pid control problems\") OR (\"api python python python programming\"))".
• Removing quotes may allow a broader search: (( coder decoder pid control problems ) OR ( api python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder decoder pid control problems") OR ("api python python python programming"))*.