Perhaps you should try some spelling variations:
"50 ngn decrease" » "50 nn decrease" (Expand Search), "50 mean decrease" (Expand Search), "50 _ decrease" (Expand Search), "50 ngnn decrease" (Expand Search), "50 ng_ decrease" (Expand Search), "50 nga decrease" (Expand Search), "50 ng decrease" (Expand Search), "50 nsgn decrease" (Expand Search), "50 nggn decrease" (Expand Search), "50 μgn decrease" (Expand Search)
"50 nga decrease" » "50 a decrease" (Expand Search), "50 nn decrease" (Expand Search), "50 mean decrease" (Expand Search), "50 ng decrease" (Expand Search), "50 nsga decrease" (Expand Search), "50 ngga decrease" (Expand Search), "50 μga decrease" (Expand Search)
"50 μgn decrease" » "50 μgnn decrease" (Expand Search), "50 μg_ decrease" (Expand Search), "50 μga 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 ngn decrease") OR ("50 μgn decrease"))) OR ("50 nga decrease"))) OR ("50 n decrease"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"50 ngn decrease\") OR (\"50 μgn decrease\"))) OR (\"50 nga decrease\"))) OR (\"50 n decrease\"))*".
• Removing quotes may allow a broader search: (((((( 50 ngn decrease ) OR ( 50 μgn decrease ))) OR ( 50 nga decrease ))) OR ( 50 n decrease ))*.