Perhaps you should try some spelling variations:
"python code implementing" » "python mode implementing" (Expand Search)
"python core implementing" » "python score implementing" (Expand Search), "python more implementing" (Expand Search), "python care implementing" (Expand Search)
"motion model represents" » "motion model represent" (Expand Search), "motion model presents" (Expand Search)

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("python code implementing") OR ("python core implementing"))) OR ("motion model represents"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"python code implementing\") OR (\"python core implementing\"))) OR (\"motion model represents\"))".
• Removing quotes may allow a broader search: (((( python code implementing ) OR ( python core implementing ))) OR ( motion model represents )).
• Adding a wildcard symbol may retrieve word variants: (((("python code implementing") OR ("python core implementing"))) OR ("motion model represents"))*.