Perhaps you should try some spelling variations:
"50 ng decrease" » "50 nn decrease" (Expand Search), "50 _ decrease" (Expand Search), "50 we decrease" (Expand Search), "50 mg decrease" (Expand Search), "10 ng decrease" (Expand Search), "5 ng decrease" (Expand Search)
"50 μ decrease" » "50 _ decrease" (Expand Search), "50 _ decreased" (Expand Search), "50 _ decreases" (Expand Search), "10 μ decrease" (Expand Search), "5 μ decrease" (Expand Search)
"50 a decrease" » "50 _ decrease" (Expand Search), "50 _ decreased" (Expand Search), "50 _ decreases" (Expand Search), "50 c decrease" (Expand Search), "5 a decrease" (Expand Search)

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"50 ng decrease\") OR (\"50 a decrease\"))) OR (\"50 μ decrease\"))~".
• Removing quotes may allow a broader search: (((( 50 ng decrease ) OR ( 50 a decrease ))) OR ( 50 μ decrease ))~.
• Adding a wildcard symbol may retrieve word variants: (((("50 ng decrease") OR ("50 a decrease"))) OR ("50 μ decrease"))*.