Perhaps you should try some spelling variations:
"communicate state" » "communicate strategy", "communicating state", "communication state"
"communicable diseases" » "communicable disease"
"complex diseases" » "complex disease"

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: (("communicable diseases") OR ((("complex diseases") OR ("communicate state")))).
• Removing quotes may allow a broader search: (( communicable diseases ) or ((( complex diseases ) or ( communicate state )))).
• Adding a wildcard symbol may retrieve word variants: (("communicable diseases") or ((("complex diseases") or ("communicate state"))))*.