Perhaps you should try some spelling variations:
augmentation techniques » segmentation techniques, imputation techniques
floatation technique » inhalation technique, implantation technique, imputation techniques
n floatation » _ floatation
gas sensor » gas sensors
based n » based _, based k, based no2

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( learning-gas sensor augmentation techniques ) OR ( learning-based n floatation technique ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( learning-gas sensor augmentation techniques ) OR ( learning-based n floatation technique ))".
• Adding a wildcard symbol may retrieve word variants: (( learning-gas sensor augmentation techniques ) OR ( learning-based n floatation technique ))*.