Perhaps you should try some spelling variations:
"electrical engineers's" » "electric engineering", "electrical engine", "electronics engineer's"
"acoustical engineering" » "optical engineering", "biomedical engineering", "industrial engineering"
"electrical engineer's" » "electrical engine", "electric engineering", "electronic engineers"
"electronics engineers" » "electronics engineering", "electronic engineering", "electrooptics engineered"
"practical engineers's" » "practical engineering", "practical engineer", "pratical 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: (((("electrical engineer's") OR ("electronics engineers"))) OR ((((("electrical engineers's") OR ((("practical engineers's") OR ("acoustical engineering"))))) OR ("electrical engineering")))).
• Removing quotes may allow a broader search: (((( electrical engineer's ) or ( electronics engineers ))) or ((((( electrical engineers's ) or ((( practical engineers's ) or ( acoustical engineering ))))) or ( electrical engineering )))).
• Adding a wildcard symbol may retrieve word variants: (((("electrical engineer's") or ("electronics engineers"))) or ((((("electrical engineers's") or ((("practical engineers's") or ("acoustical engineering"))))) or ("electrical engineering"))))*.