Perhaps you should try some spelling variations:
"nature et social work." » "nature et social workers.", "nature et sociales work.", "nature 1 social work.", "nature 11 social work.", "nature det social work.", "nature ent social work.", "nature ret social work."
"nature _ social work." » "nature _ social workers."
"nature e social sectors." » "nature de social sectors.", "nature en social sectors.", "nature re social sectors.", "nature e sociali sectors.", "nature use social sectors.", "nature age social sectors.", "nature e social sector."

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 social work.") OR ("nature _ social work."))) or ("nature e social sectors."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("nature et social work.") OR ("nature _ social work."))) OR ("nature e social sectors.")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"nature et social work.\") OR (\"nature _ social work.\"))) or (\"nature e social sectors.\"))".
• Removing quotes may allow a broader search: (((( nature et social work. ) OR ( nature _ social work. ))) or ( nature e social sectors. )).
• Adding a wildcard symbol may retrieve word variants: (((("nature et social work.") OR ("nature _ social work."))) or ("nature e social sectors."))*.