Perhaps you should try some spelling variations:
"50 nn decrease" » "50 _ decrease" (Expand Search)
"_ we decrease" » "_ _ decrease" (Expand Search), "_ web decrease" (Expand Search), "_ e decrease" (Expand Search), "_ fe decrease" (Expand Search)
"5 ht decrease" » "5 _ decrease" (Expand Search)
"_ eb decrease" » "_ _ decrease" (Expand Search), "_ web decrease" (Expand Search), "_ ebv decrease" (Expand Search), "_ ebm 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 nn decrease\") OR (((((\"_ we decrease\") OR (\"5 ht decrease\"))) OR (\"_ eb decrease\"))))~".
• Removing quotes may allow a broader search: (( 50 nn decrease ) OR ((((( _ we decrease ) OR ( 5 ht decrease ))) OR ( _ eb decrease ))))~.
• Adding a wildcard symbol may retrieve word variants: (("50 nn decrease") OR ((((("_ we decrease") OR ("5 ht decrease"))) OR ("_ eb decrease"))))*.