Perhaps you should try some spelling variations:
"coder string exchange algorithm complexity" » "coder string exchange algorithms complexity" (Expand search), "coder string exchange algorithmic complexity" (Expand search), "coder syringe exchange algorithm complexity" (Expand search), "coder sharing exchange algorithm complexity" (Expand search), "coder during exchange algorithm complexity" (Expand search), "cordel string exchange algorithm complexity" (Expand search), "closed string exchange algorithm complexity" (Expand search), "modelo string exchange algorithm complexity" (Expand search)
"api _ python python programming" » "api _ pythons python programming" (Expand search), "api _ piton python programming" (Expand search), "api _ pitons 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 string exchange algorithm complexity") OR ("api _ python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder string exchange algorithm complexity\") OR (\"api _ python python programming\"))".
• Removing quotes may allow a broader search: (( coder string exchange algorithm complexity ) OR ( api _ python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder string exchange algorithm complexity") OR ("api _ python python programming"))*.