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