Perhaps you should try some spelling variations:
"nature _ social sector." » "nature _ social sectors."
"nature et society ser." » "nature et society sector.", "nature et society work.", "nature _ society ser.", "nature open society ser.", "nature host society ser.", "nature at society ser."
"nature e society ser." » "nature e society sector.", "nature e society work.", "nature _ society ser.", "nature open society ser.", "nature a society ser."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("nature et society ser.") or ("nature e society ser."))) or ("nature _ social sector."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("nature et society ser.") OR ("nature e society ser."))) OR ("nature _ social sector.")).
• Removing quotes may allow a broader search: (((( nature et society ser. ) or ( nature e society ser. ))) or ( nature _ social sector. )).
• Adding a wildcard symbol may retrieve word variants: (((("nature et society ser.") or ("nature e society ser."))) or ("nature _ social sector."))*.