Perhaps you should try some spelling variations:
"coder coder sampling cost problem" » "coder under sampling cost problem" (Expand search), "coder over sampling cost problem" (Expand search), "coder core sampling cost problem" (Expand search), "coder coder sampling forest problem" (Expand search), "coder coder sampling down problem" (Expand search), "coder coder sampling gas problem" (Expand search), "coder coder sampling cut problem" (Expand search), "coder coder sampling about problem" (Expand search), "coder decoder sampling cost problem" (Expand search), "code code sampling cost problem" (Expand search), "decoder codec sampling cost problem" (Expand search)
"on python python python programming" » "on pythons python python programming" (Expand search), "on piton python python programming" (Expand search), "on pitons python python programming" (Expand search), "in python pythin python programming" (Expand search), "of python pythof python programming" (Expand search), "_ python pyth_ 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 sampling cost problem") OR ("on python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder sampling cost problem\") OR (\"on python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coder sampling cost problem ) OR ( on python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coder sampling cost problem") OR ("on python python python programming"))*.