Perhaps you should try some spelling variations:
"clean development strategies." » "clean development strategy.", "human development strategies.", "urban development strategies."
"a development series." » "a development services.", "a development agencies.", "a development strategy."
"_ development series." » "_ development services.", "_ development agencies.", "_ development strategy."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("clean development strategies.") or ((("a development series.") OR ("_ development series."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("clean development strategies.") OR ((("a development series.") OR ("_ development series."))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"clean development strategies.\") or (((\"a development series.\") OR (\"_ development series.\"))))*".
• Removing quotes may allow a broader search: (( clean development strategies. ) or ((( a development series. ) OR ( _ development series. ))))*.