Perhaps you should try some spelling variations:
"5 ppm decrease" » "5 _ decrease" (Expand Search)
"_ nn decrease" » "_ _ decrease" (Expand Search), "_ ann decrease" (Expand Search), "_ cnn decrease" (Expand Search), "_ knn decrease" (Expand Search)
"59 nn decrease" » "59 _ decrease" (Expand Search)
"_ points decrease" » "_ point decrease" (Expand Search), "a point decrease" (Expand Search), "5 point decrease" (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: "((\"5 ppm decrease\") OR (((((\"_ nn decrease\") OR (\"59 nn decrease\"))) OR (\"_ points decrease\"))))~".
• Removing quotes may allow a broader search: (( 5 ppm decrease ) OR ((((( _ nn decrease ) OR ( 59 nn decrease ))) OR ( _ points decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (("5 ppm decrease") OR ((((("_ nn decrease") OR ("59 nn decrease"))) OR ("_ points decrease"))))*.