Perhaps you should try some spelling variations:
"clean development studies." » "clean development services.", "clean development strategies.", "clean development strategy.", "human development studies.", "urban development studies."
"a development series." » "a development services.", "a development agencies.", "a development strategies."
"city development series." » "city development services.", "city development agencies.", "city development strategies.", "capacity development series.", "policy development series.", "community development series."

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