Perhaps you should try some spelling variations:
"50 pp decrease" » "50 pp decreased" (Expand Search), "50 pp increase" (Expand Search)
"k nn decrease" » "k nn decreased" (Expand Search), "k nn increase" (Expand Search)
"5 fold decrease" » "5 fold decreased" (Expand Search), "5 fold increase" (Expand Search), "5 food decrease" (Expand Search), "5 old decrease" (Expand Search)
"5 a decrease" » "5 a decreased" (Expand Search), "5 a increase" (Expand Search)

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"50 pp decrease\") OR (((((\"k nn decrease\") OR (\"5 fold decrease\"))) OR (\"5 a decrease\"))))~".
• Removing quotes may allow a broader search: (( 50 pp decrease ) OR ((((( k nn decrease ) OR ( 5 fold decrease ))) OR ( 5 a decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (("50 pp decrease") OR ((((("k nn decrease") OR ("5 fold decrease"))) OR ("5 a decrease"))))*.