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