Perhaps you should try some spelling variations:
decrease operational » increase operational (Expand search), disease operational (Expand search), decrease cooperation (Expand search)
operational process » operational processes (Expand search), operacional processos (Expand search), operational problems (Expand search)
decrease akt » decrease at (Expand search), decrease and (Expand search), decrease after (Expand search)
akt decrease » and decrease (Expand search), not decrease (Expand search), any decrease (Expand search)
decrease toc » decrease of (Expand search), decrease the (Expand search), decreased to (Expand search)
toc decrease » to decrease (Expand search), the decrease (Expand search), not decrease (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 OR decrease operational process ) OR ( decrease akt decrease toc decrease ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease OR decrease operational process ) OR ( decrease akt decrease toc decrease ))*.