Perhaps you should try some spelling variations:
"mechanical engineering discoveries" » "mechanical engineering discovering", "mechanical engineering discovery", "mechanical engineering fisheries", "electrical engineering discoveries"
"mechanical engineering proceedings" » "electrical engineering proceedings"

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: (("mechanical engineering proceedings") OR ("mechanical engineering discoveries")).
• Removing quotes may allow a broader search: (( mechanical engineering proceedings ) or ( mechanical engineering discoveries )).
• Adding a wildcard symbol may retrieve word variants: (("mechanical engineering proceedings") or ("mechanical engineering discoveries"))*.