Perhaps you should try some spelling variations:
"50 pp decrease" » "50 _ decrease" (Expand Search)
"50 we decrease" » "50 _ decrease" (Expand Search)
"5 ng decrease" » "5 _ decrease" (Expand Search), "5 g decrease" (Expand Search), "5 μg decrease" (Expand Search)
"50 a decrease" » "50 _ decrease" (Expand Search), "50 _ decreased" (Expand Search), "50 _ decreases" (Expand Search), "5 a decrease" (Expand Search), "50 i decrease" (Expand Search)

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("50 pp decrease") OR ("50 a decrease"))) OR ((("50 we decrease") OR ("5 ng decrease"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"50 pp decrease\") OR (\"50 a decrease\"))) OR (((\"50 we decrease\") OR (\"5 ng decrease\"))))*".
• Removing quotes may allow a broader search: (((( 50 pp decrease ) OR ( 50 a decrease ))) OR ((( 50 we decrease ) OR ( 5 ng decrease ))))*.