Perhaps you should try some spelling variations:
"5 ppm decrease" » "5 _ decrease" (Expand Search), "5 a decrease" (Expand Search), "5 pa decreased" (Expand Search)
"5 nn decrease" » "5 _ decrease" (Expand Search), "5 a decrease" (Expand Search), "5 mean decrease" (Expand Search), "5 non decrease" (Expand Search), "59 nn decrease" (Expand Search), "5 nm decrease" (Expand Search)
"50 ns decrease" » "50 _ decrease" (Expand Search), "50 a decrease" (Expand Search), "50 we decrease" (Expand Search), "50 ms decrease" (Expand Search)
"5 ng decrease" » "5 _ decrease" (Expand Search), "5 a decrease" (Expand Search), "5 we decrease" (Expand Search), "5 mg decrease" (Expand Search), "5 g decrease" (Expand Search), "5 nm decrease" (Expand Search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("5 ppm decrease") OR ("5 nn decrease"))) OR ((("50 ns decrease") OR ("5 ng decrease"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"5 ppm decrease\") OR (\"5 nn decrease\"))) OR (((\"50 ns decrease\") OR (\"5 ng decrease\"))))".
• Removing quotes may allow a broader search: (((( 5 ppm decrease ) OR ( 5 nn decrease ))) OR ((( 50 ns decrease ) OR ( 5 ng decrease )))).
• Adding a wildcard symbol may retrieve word variants: (((("5 ppm decrease") OR ("5 nn decrease"))) OR ((("50 ns decrease") OR ("5 ng decrease"))))*.