Perhaps you should try some spelling variations:
"_ feb decrease" » "_ _ decrease" (Expand Search), "_ web decrease" (Expand Search), "_ fed decrease" (Expand Search), "_ fes decrease" (Expand Search)
"10 ng decrease" » "10 _ decrease" (Expand Search), "100 ng decrease" (Expand Search), "10 μg decrease" (Expand Search)
"_ we decrease" » "_ _ decrease" (Expand Search), "_ w_ decrease" (Expand Search), "_ w_ decreased" (Expand Search), "_ w_ decreases" (Expand Search), "_ web decrease" (Expand Search), "_ e decrease" (Expand Search), "_ fe decrease" (Expand Search)
"5 e 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: "((\"10 ng decrease\") OR (((((\"_ we decrease\") OR (\"5 e decrease\"))) OR (\"_ feb decrease\"))))~".
• Removing quotes may allow a broader search: (( 10 ng decrease ) OR ((((( _ we decrease ) OR ( 5 e decrease ))) OR ( _ feb decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (("10 ng decrease") OR ((((("_ we decrease") OR ("5 e decrease"))) OR ("_ feb decrease"))))*.