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