Perhaps you should try some spelling variations:
development series » development services, development agencies, development africa
technical experts » technical expertise
sea environmental » weak environmental, state environmental, sites environmental
key environmental » _ environmental, 2 environmental
sustainable rural » sustainable urban, sustainable use, sustainable resource
rural development » social development
technical paper » technical report

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: world bank ((technical paper) OR (technical experts)). europe AND central ((sea environmental) OR (key environmental)) AND socially sustainable rural development series.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "world bank ((technical paper) OR (technical experts)). europe and central ((sea environmental) or (key environmental)) and socially sustainable rural development series.~".
• Adding a wildcard symbol may retrieve word variants: world bank ((technical paper) OR (technical experts)). europe and central ((sea environmental) or (key environmental)) and socially sustainable rural development series.*.