Perhaps you should try some spelling variations:
imputation techniques » implantation technique, augmentation techniques, segmentation techniques
inhalation technique » floatation technique, implantation technique, inhaler technique
k inhalation » _ inhalation, k inflation, _ inflation
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 inhalation technique ) OR ( learning-based no2 imputation techniques ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( learning-based k inhalation technique ) OR ( learning-based no2 imputation techniques ))".
• Adding a wildcard symbol may retrieve word variants: (( learning-based k inhalation technique ) OR ( learning-based no2 imputation techniques ))*.