Perhaps you should try some spelling variations:
"pollution dimensions reduction" » "position dimensions reduction", "solutions dimensions reduction", "evaluation dimensions reduction", "pollution dimensional reduction", "pollution dimension reductions", "pollution dimensional reductions"
"pollutant dimension reduction" » "pollutant dispersion reduction", "pollutants dispersion reduction", "pollutant emission reduction", "pollutant dimensionality reduction"
"pollutant diffusion reduction" » "pollutant dispersion reduction", "constant diffusion reduction", "pollutants dispersion reduction", "pollutant diffusion prediction", "pollutant diffusion reaction", "pollutant diffusion reflection"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("pollutant dimension reduction") OR ("pollution dimensions reduction"))) OR ("pollutant diffusion reduction")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"pollutant dimension reduction\") OR (\"pollution dimensions reduction\"))) or (\"pollutant diffusion reduction\"))".
• Removing quotes may allow a broader search: (((( pollutant dimension reduction ) OR ( pollution dimensions reduction ))) or ( pollutant diffusion reduction )).
• Adding a wildcard symbol may retrieve word variants: (((("pollutant dimension reduction") OR ("pollution dimensions reduction"))) or ("pollutant diffusion reduction"))*.