Perhaps you should try some spelling variations:
"greater decrease" » "greater decreased" (Expand Search), "greater increase" (Expand Search)
"per decrease" » "per decreased" (Expand Search), "per increase" (Expand Search)
"smeeth decrease" » "smeeth decreased" (Expand Search), "smeeth increase" (Expand Search), "smeets decrease" (Expand Search)
"pearson decrease" » "pearson decreased" (Expand Search), "pearson increase" (Expand Search), "person decrease" (Expand Search)

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("greater decrease") OR ((("per decrease") OR ((("smeeth decrease") OR ("pearson decrease"))))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"greater decrease\") OR (((\"per decrease\") OR (((\"smeeth decrease\") OR (\"pearson decrease\"))))))".
• Removing quotes may allow a broader search: (( greater decrease ) OR ((( per decrease ) OR ((( smeeth decrease ) OR ( pearson decrease )))))).
• Adding a wildcard symbol may retrieve word variants: (("greater decrease") OR ((("per decrease") OR ((("smeeth decrease") OR ("pearson decrease"))))))*.