Perhaps you should try some spelling variations:
"communicate diseases" » "communicable diseases", "communicate disabled", "communicate discover"
"communicable disease" » "communicable diseases"
"communicated disease" » "communicable diseases", "communicate state", "communicated vision"
"complicated diseases" » "complicated cases", "complex diseases", "complicated case"
"mediated diseases" » "related diseases", "medical diseases", "related 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: (((("communicate diseases") OR ("communicable disease"))) OR ((((("communicated disease") OR ("complicated diseases"))) OR ("mediated diseases")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"communicate diseases\") or (\"communicable disease\"))) or (((((\"communicated disease\") OR (\"complicated diseases\"))) or (\"mediated diseases\"))))".
• Removing quotes may allow a broader search: (((( communicate diseases ) or ( communicable disease ))) or ((((( communicated disease ) OR ( complicated diseases ))) or ( mediated diseases )))).
• Adding a wildcard symbol may retrieve word variants: (((("communicate diseases") or ("communicable disease"))) or ((((("communicated disease") OR ("complicated diseases"))) or ("mediated diseases"))))*.