Perhaps you should try some spelling variations:
"voluntary sector briefing : december 2010" » "voluntary export briefing : december 2010", "voluntary sector briefing : december 2013", "voluntary sector briefing : november 2010"
"voluntary sector borrowing : december 2017" » "voluntary export borrowing : december 2017"

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: "((\"voluntary sector briefing : december 2010\") OR (\"voluntary sector borrowing : december 2017\"))~".
• Removing quotes may allow a broader search: (( voluntary sector briefing : december 2010 ) OR ( voluntary sector borrowing : december 2017 ))~.
• Adding a wildcard symbol may retrieve word variants: (("voluntary sector briefing : december 2010") OR ("voluntary sector borrowing : december 2017"))*.