Perhaps you should try some spelling variations:
decrease treg » decrease their (Expand search)
decrease the » decreases the (Expand search), decrease in (Expand search), decrease of (Expand search)
the decrease » to decrease (Expand search), and decrease (Expand search)
decrease toc » decrease of (Expand search), decreased to (Expand search), decrease on (Expand search)
toc decrease » to decrease (Expand search), not decrease (Expand search), or decrease (Expand search)
treg based » tree based (Expand search), reg based (Expand search), trees based (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 _ decrease the decrease ) OR ( decrease toc decrease treg based ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease _ decrease the decrease ) OR ( decrease toc decrease treg based ))*.