Perhaps you should try some spelling variations:
"50 nsn decrease" » "50 nn decrease" (Expand Search), "50 mean decrease" (Expand Search), "50 use decreased" (Expand Search), "50 nsnn decrease" (Expand Search), "50 ns_ decrease" (Expand Search), "50 nsa decrease" (Expand Search), "50 ns decrease" (Expand Search), "50 nssn decrease" (Expand Search), "50 ngsn decrease" (Expand Search), "50 μsn decrease" (Expand Search)
"50 μn decrease" » "50 μnn decrease" (Expand Search), "50 μ_ decrease" (Expand Search), "50 μa decrease" (Expand Search)
"50 n decrease" » "50 nn decrease" (Expand Search), "50 _ decrease" (Expand Search), "50 a decrease" (Expand Search), "50 ns decrease" (Expand Search), "50 ng decrease" (Expand Search), "50 μ 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 μn decrease") OR ("50 nsn decrease"))) OR ("50 n decrease"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"50 μn decrease\") OR (\"50 nsn decrease\"))) OR (\"50 n decrease\"))*".
• Removing quotes may allow a broader search: (((( 50 μn decrease ) OR ( 50 nsn decrease ))) OR ( 50 n decrease ))*.