Perhaps you should try some spelling variations:
"5 ppm decrease" » "5 _ decrease" (Expand Search), "5 nn decrease" (Expand Search), "5 pa decreased" (Expand Search)
"5 026 decrease" » "5 _ decrease" (Expand Search), "5 nn decrease" (Expand Search), "n 026 decrease" (Expand Search)
"50 ns decrease" » "50 nn decrease" (Expand Search), "50 _ decrease" (Expand Search), "50 we decrease" (Expand Search), "50 ms decrease" (Expand Search)
"5 a decrease" » "5 _ decrease" (Expand Search), "5 _ decreased" (Expand Search), "5 _ decreases" (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 (\"50 ns decrease\"))) OR (((\"5 026 decrease\") OR (\"5 a decrease\"))))~".
• Removing quotes may allow a broader search: (((( 5 ppm decrease ) OR ( 50 ns decrease ))) OR ((( 5 026 decrease ) OR ( 5 a decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (((("5 ppm decrease") OR ("50 ns decrease"))) OR ((("5 026 decrease") OR ("5 a decrease"))))*.