Perhaps you should try some spelling variations:
"learning-based no2 segmentation techniques" » "learning-based no2 augmentation techniques", "learning-based no2 imputation techniques", "learning-based 3d segmentation techniques", "learning-based co segmentation techniques", "learning-based n segmentation techniques"
"learning-based novel reduction techniques" » "learning-based novel reduction technique", "learning-based novel imputation techniques", "learning-based model reduction techniques", "learning-based poverty reduction techniques", "learning-based closed reduction techniques", "learning-based anodes reduction techniques"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("learning-based no2 segmentation techniques") OR ("learning-based novel reduction techniques"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"learning-based no2 segmentation techniques\") OR (\"learning-based novel reduction techniques\"))*".
• Removing quotes may allow a broader search: (( learning-based no2 segmentation techniques ) OR ( learning-based novel reduction techniques ))*.