Perhaps you should try some spelling variations:
increased litter » increased winter (Expand search), increased after (Expand search), increased water (Expand search)
decrease during » increase during (Expand search), increases during (Expand search), increased during (Expand search)
during decrease » during increased (Expand search), during depressed (Expand search), during disease (Expand search)
litter affects » clutter affects (Expand search), litter affected (Expand search), litter effect (Expand search)
decrease rate » decreased rate (Expand search), decreases rate (Expand search), decrease at (Expand search)
rate decrease » rats decreases (Expand search), rate increase (Expand search), to decrease (Expand search)
the increased » the increase (Expand search), to increased (Expand search), and increased (Expand search)
decrease the » decreases the (Expand search), decrease in (Expand search), decrease of (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: "(( decrease during decrease rate decrease ) OR ( decrease the increased litter affects ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease during decrease rate decrease ) OR ( decrease the increased litter affects ))*.