Perhaps you should try some spelling variations:
"_ we decrease" » "_ _ decrease" (Expand Search), "_ web decrease" (Expand Search), "_ e decrease" (Expand Search), "_ wt decrease" (Expand Search)
"_ fe decrease" » "_ _ decrease" (Expand Search), "_ e decrease" (Expand Search)
"50 ng decrease" » "50 _ decrease" (Expand Search), "10 ng decrease" (Expand Search), "50 μg decrease" (Expand Search)
"5 a decrease" » "5 _ decrease" (Expand Search), "5 _ decreased" (Expand Search), "5 _ decreases" (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: "((\"5 a decrease\") OR (((((\"_ we decrease\") OR (\"_ fe decrease\"))) OR (\"50 ng decrease\"))))~".
• Removing quotes may allow a broader search: (( 5 a decrease ) OR ((((( _ we decrease ) OR ( _ fe decrease ))) OR ( 50 ng decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (("5 a decrease") OR ((((("_ we decrease") OR ("_ fe decrease"))) OR ("50 ng decrease"))))*.