Perhaps you should try some spelling variations:
"electrical engineer's" » "electrical engine", "electric engineering", "electronics engineers"
"electrical engineers" » "mechanical engineers", "chemical engineers"
"optical engineering" » "chemical engineering", "biomedical engineering"

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: (("optical engineering") OR ((((("electrical engineer's") OR ("electrical engineers"))) OR ("electrical engineering")))).
• Removing quotes may allow a broader search: (( optical engineering ) or ((((( electrical engineer's ) or ( electrical engineers ))) or ( electrical engineering )))).
• Adding a wildcard symbol may retrieve word variants: (("optical engineering") or ((((("electrical engineer's") or ("electrical engineers"))) or ("electrical engineering"))))*.