Perhaps you should try some spelling variations:
"coder decoder precoder design problem" » "coder encoder decoder design problem" (Expand search), "coder decoder codec design problem" (Expand search), "coder decoder precoding design problem" (Expand search), "encoder decoder precoder design problem" (Expand search)
"_ python python python programming" » "_ pythons python python programming" (Expand search), "_ piton python python programming" (Expand search), "_ 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 precoder design problem") OR ("_ python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder decoder precoder design problem\") OR (\"_ python python python programming\"))".
• Removing quotes may allow a broader search: (( coder decoder precoder design problem ) OR ( _ python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder decoder precoder design problem") OR ("_ python python python programming"))*.