Perhaps you should try some spelling variations:
"learning-based 3do2 imputation techniques" » "learning-based 3do2 implantation technique", "learning-based 3do2 augmentation techniques", "learning-based 3do2 segmentation techniques", "learning-based 3d imputation techniques", "learning-based no2 imputation techniques"
"learning-based k reduction technique" » "learning-based k reduction techniques", "learning-based k truncation technique", "learning-based _ reduction technique", "learning-based _ prediction technique", "learning-based _ production technique", "learning-based n reduction technique", "learning-based 3d reduction technique"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"learning-based 3do2 imputation techniques\") OR (\"learning-based k reduction technique\"))~".
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