Perhaps you should try some spelling variations:
"5 ppm decrease" » "5 _ decrease" (Expand Search)
"50 ns decrease" » "50 _ decrease" (Expand Search)
"5 nn decrease" » "5 _ decrease" (Expand Search), "k nn decrease" (Expand Search), "_ nn 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: (((("5 ppm decrease") OR ((("50 a decrease") OR ("50 ns decrease"))))) OR ("5 nn decrease"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"5 ppm decrease\") OR (((\"50 a decrease\") OR (\"50 ns decrease\"))))) OR (\"5 nn decrease\"))*".
• Removing quotes may allow a broader search: (((( 5 ppm decrease ) OR ((( 50 a decrease ) OR ( 50 ns decrease ))))) OR ( 5 nn decrease ))*.