Perhaps you should try some spelling variations:
proceedings 2nd » proceedings 2000, proceedings 2001, proceedings 2003
proceedings el » proceedings ed, proceedings etc, proceedings 2
proceedings ec » proceedings etc, proceedings 2, proceedings 1

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: ((((proceedings el) OR (proceedings 2nd))) OR (proceedings ec)) report.
• Adding a wildcard symbol may retrieve word variants: ((((proceedings el) or (proceedings 2nd))) or (proceedings ec)) report*.