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

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