Perhaps you should try some spelling variations:
complicated diseases » complicated cases, complex diseases, mediated diseases
communicate diseases » communicable disease, communicate disabled, communicate discover
communicated disease » communicable disease, communicate state, communicated vision

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 ( complicated diseases ))))) OR ( communicated disease )).
• Adding a wildcard symbol may retrieve word variants: (((( communicable diseases ) or ((( communicate diseases ) or ( complicated diseases ))))) or ( communicated disease ))*.