Perhaps you should try some spelling variations:
employee » employed
employees » employeds
co-cooperatives" » co-cooperative", co-cooperation", co-cooperating"
co-operativen" » co-operative", co-operation"

Try widening your search to All Fields.

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: (("(employee OR employees)-ownership & (co-cooperatives" or co-operativen")) OR ("(employee or employees)-ownership & co-operations")).
• Removing quotes may allow a broader search: (( (employee or employees)-ownership & (co-cooperatives or co-operativen )) or ( (employee or employees)-ownership & co-operations )).
• Adding a wildcard symbol may retrieve word variants: (("(employee or employees)-ownership & (co-cooperatives" or co-operativen")) or ("(employee or employees)-ownership & co-operations"))*.