Perhaps you should try some spelling variations:
"coder coder subspace indexing problem" » "coder coder subject indexing problem" (Expand search), "coder coder subspace ordering problem" (Expand search), "coder coder subspace increasing problem" (Expand search), "coder coder subspace filtering problem" (Expand search), "coder decoder subspace indexing problem" (Expand search), "code code subspace indexing problem" (Expand search), "decoder codec subspace indexing 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 coder subspace indexing problem") OR ("_ python python python programming"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"coder coder subspace indexing problem\") OR (\"_ python python python programming\"))".
• Removing quotes may allow a broader search: (( coder coder subspace indexing problem ) OR ( _ python python python programming )).
• Adding a wildcard symbol may retrieve word variants: (("coder coder subspace indexing problem") OR ("_ python python python programming"))*.