Perhaps you should try some spelling variations:
"coder coder learning units problem" » "coder codes learning units problem" (Expand search), "coder modern learning units problem" (Expand search), "coder model learning units problem" (Expand search), "coder coder learning unit problem" (Expand search), "coder coder learning using problem" (Expand search), "coder coder learning under problem" (Expand search), "coder coder learning its problem" (Expand search), "coder coder learning its problems" (Expand search), "coder decoder learning units problem" (Expand search), "code code learning units problem" (Expand search), "decoder codec learning units 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 learning units problem") OR ("on python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder learning units problem\") OR (\"on python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coder learning units problem ) OR ( on python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coder learning units problem") OR ("on python python python programming"))*.