Perhaps you should try some spelling variations:
floatation technique » inhalation technique, implantation technique, imputation techniques
reduction technique » reduction techniques, truncation technique
no2 floatation » _ floatation
two reduction » h2o2 reduction, _ reduction
based no2 » based co, based n
based two » based tool, based co

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