Perhaps you should try some spelling variations:
"5 nn decrease" » "k nn decrease" (Expand Search), "_ nn decrease" (Expand Search), "5 nn decreased" (Expand Search), "5 nn increase" (Expand Search)
"5 a decrease" » "5 a decreased" (Expand Search), "5 a increase" (Expand Search)
"5 fold decrease" » "5 fold decreased" (Expand Search), "5 fold increase" (Expand Search), "5 food decrease" (Expand Search), "5 old decrease" (Expand Search)
"6 nm decrease" » "6 nm decreased" (Expand Search), "6 nm increase" (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 a decrease\") OR (((\"5 fold decrease\") OR (((\"6 nm decrease\") OR (\"5 nn decrease\"))))))~".
• Removing quotes may allow a broader search: (( 5 a decrease ) OR ((( 5 fold decrease ) OR ((( 6 nm decrease ) OR ( 5 nn decrease ))))))~.
• Adding a wildcard symbol may retrieve word variants: (("5 a decrease") OR ((("5 fold decrease") OR ((("6 nm decrease") OR ("5 nn decrease"))))))*.