Perhaps you should try some spelling variations:
"communicated diseases" » "communicated disease", "communicable disease", "communicate disabled"
"complicated diseases" » "complicated cases", "complex diseases"
"mediated diseases" » "related diseases", "medical diseases", "related disease"
"complicated case" » "complicated cases", "complicated acute", "complicated chapter"

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: (((("communicated diseases") OR ("communicable diseases"))) OR ((((("complicated diseases") OR ("complicated case"))) OR ("mediated diseases"))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"communicated diseases\") or (\"communicable diseases\"))) or (((((\"complicated diseases\") OR (\"complicated case\"))) or (\"mediated diseases\"))))*".
• Removing quotes may allow a broader search: (((( communicated diseases ) or ( communicable diseases ))) or ((((( complicated diseases ) OR ( complicated case ))) or ( mediated diseases ))))*.