Perhaps you should try some spelling variations:
"50 ng decrease" » "50 a decrease" (Expand Search), "50 we decrease" (Expand Search), "50 gy decreased" (Expand Search), "50 mg decrease" (Expand Search), "10 ng decrease" (Expand Search), "5 ng decrease" (Expand Search)
"5 nm decrease" » "5 a decrease" (Expand Search), "5 we decrease" (Expand Search), "5 gy decreased" (Expand Search), "5 mm decrease" (Expand Search), "5 cm decrease" (Expand Search)
"5 nn decrease" » "5 a decrease" (Expand Search), "5 mean decrease" (Expand Search), "5 gy decreased" (Expand Search), "5 non decrease" (Expand Search), "59 nn decrease" (Expand Search), "5 n 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 _ decrease\") OR (((\"50 ng decrease\") OR (((\"5 nm decrease\") OR (\"5 nn decrease\"))))))~".
• Removing quotes may allow a broader search: (( 50 _ decrease ) OR ((( 50 ng decrease ) OR ((( 5 nm decrease ) OR ( 5 nn decrease ))))))~.
• Adding a wildcard symbol may retrieve word variants: (("50 _ decrease") OR ((("50 ng decrease") OR ((("5 nm decrease") OR ("5 nn decrease"))))))*.