Perhaps you should try some spelling variations:
"middle east's / history" » "middle eastern / history", "middle ears / history", "middle earth / history"
"middle layer / history" » "middle ages / history", "middle aged / history", "middle age / history"

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: (("middle east's / history") OR ("middle layer / history")).
• Removing quotes may allow a broader search: (( middle east's / history ) or ( middle layer / history )).
• Adding a wildcard symbol may retrieve word variants: (("middle east's / history") or ("middle layer / history"))*.