Perhaps you should try some spelling variations:
"helped decrease" » "helped decreased" (Expand Search), "helped increase" (Expand Search)
"meters decrease" » "meters decreased" (Expand Search), "meters increase" (Expand Search)
"speer decrease" » "speer decreased" (Expand Search), "speer increase" (Expand Search), "speed decrease" (Expand Search), "peer decrease" (Expand Search), "steer decrease" (Expand Search)
"mean decrease" » "mean decreased" (Expand Search), "mean increase" (Expand Search)

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("helped decrease") OR ((("meters decrease") OR ("speer decrease"))))) OR ("mean decrease"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"helped decrease\") OR (((\"meters decrease\") OR (\"speer decrease\"))))) OR (\"mean decrease\"))".
• Removing quotes may allow a broader search: (((( helped decrease ) OR ((( meters decrease ) OR ( speer decrease ))))) OR ( mean decrease )).
• Adding a wildcard symbol may retrieve word variants: (((("helped decrease") OR ((("meters decrease") OR ("speer decrease"))))) OR ("mean decrease"))*.