Perhaps you should try some spelling variations:
imputation techniques » implantation technique, augmentation techniques, segmentation techniques
floatation technique » inhalation technique, implantation technique, truncation technique
k floatation » _ floatation
based no2 » based co, based n
based k » based _, based n, based 3d

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 k floatation technique ) or ( learning-based no2 imputation techniques ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( learning-based k floatation technique ) OR ( learning-based no2 imputation techniques )).
• Adding a wildcard symbol may retrieve word variants: (( learning-based k floatation technique ) or ( learning-based no2 imputation techniques ))*.