Perhaps you should try some spelling variations:
mitigation techniques » imputation techniques
floatation technique » inhalation technique, implantation technique, imputation techniques
no2 floatation » _ floatation
k mitigation » _ mitigation, _ litigation
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 no2 floatation technique ) or ( learning-based k mitigation techniques ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( learning-based no2 floatation technique ) OR ( learning-based k mitigation techniques )).
• Adding a wildcard symbol may retrieve word variants: (( learning-based no2 floatation technique ) or ( learning-based k mitigation techniques ))*.