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