Perhaps you should try some spelling variations:
decrease yiel » decreases yield (Expand search), decrease il (Expand search), increase yield (Expand search)
decrease not » decrease of (Expand search), decrease akt (Expand search), decrease at (Expand search)
not decrease » to decrease (Expand search), not increase (Expand search), the decrease (Expand search)
decrease and » decreases and (Expand search), decrease of (Expand search), decrease the (Expand search)
and decrease » and decreases (Expand search), and decreased (Expand search), and increase (Expand search)
yiel pattern » yield pattern (Expand search), diel pattern (Expand search), diel patterns (Expand search)
in decrease » in decreased (Expand search), on decrease (Expand search), pain decrease (Expand search)

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( decrease NOT decrease in decrease ) OR ( decrease AND decrease yiel pattern ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decrease not decrease in decrease ) OR ( decrease and decrease yiel pattern ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease not decrease in decrease ) OR ( decrease and decrease yiel pattern ))*.