Perhaps you should try some spelling variations:
"5 ng decrease" » "5 _ decrease" (Expand Search), "5 g decrease" (Expand Search), "5 μg decrease" (Expand Search)
"_ fe decrease" » "_ _ decrease" (Expand Search), "_ e decrease" (Expand Search)
"_ eb decrease" » "_ _ decrease" (Expand Search), "_ web decrease" (Expand Search), "_ ebv decrease" (Expand Search), "_ ebm decrease" (Expand Search)
"2 wt decrease" » "2 _ decrease" (Expand Search), "_ wt decrease" (Expand Search), "i wt 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: "((\"5 ng decrease\") OR (((((\"_ fe decrease\") OR (\"_ eb decrease\"))) OR (\"2 wt decrease\"))))~".
• Removing quotes may allow a broader search: (( 5 ng decrease ) OR ((((( _ fe decrease ) OR ( _ eb decrease ))) OR ( 2 wt decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (("5 ng decrease") OR ((((("_ fe decrease") OR ("_ eb decrease"))) OR ("2 wt decrease"))))*.