Perhaps you should try some spelling variations:
ppm decrease » pa decreased (Expand Search), 026 decrease (Expand Search), we decrease (Expand Search)
nn decrease » mean decrease (Expand Search), gy decreased (Expand Search), b1 decreased (Expand Search)
a decrease » _ decreased (Expand Search), _ decreases (Expand Search)
_ decrease » _ decreased (Expand Search)
50 ppm » 5 ppm (Expand Search)
50 nn » 50 ns (Expand Search), 50 ng (Expand Search), 50 n (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 ppm decrease ) OR ( 50 nn decrease ))) OR ( 50 ((a decrease) OR (_ decrease)) ))~".
• Adding a wildcard symbol may retrieve word variants: (((( 50 ppm decrease ) OR ( 50 nn decrease ))) OR ( 50 ((a decrease) OR (_ decrease)) ))*.