Perhaps you should try some spelling variations:
"5 ppm decrease" » "5 _ decrease" (Expand Search), "5 a decrease" (Expand Search), "5 pa decreased" (Expand Search)
"50 nn decrease" » "50 _ decrease" (Expand Search), "50 a decrease" (Expand Search), "50 mean decrease" (Expand Search), "50 ns decrease" (Expand Search), "50 ng decrease" (Expand Search), "50 n decrease" (Expand Search)
"10 nm decrease" » "10 _ decrease" (Expand Search), "10 a decrease" (Expand Search), "10 we decrease" (Expand Search), "100 nm decrease" (Expand Search), "10 mm 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 ((("50 nn decrease") OR ((("10 nm decrease") OR ("5 ng decrease"))))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"5 ppm decrease\") OR (((\"50 nn decrease\") OR (((\"10 nm decrease\") OR (\"5 ng decrease\"))))))*".
• Removing quotes may allow a broader search: (( 5 ppm decrease ) OR ((( 50 nn decrease ) OR ((( 10 nm decrease ) OR ( 5 ng decrease ))))))*.