Perhaps you should try some spelling variations:
network synthesis » network systems
health evidence » health science
systems report » systems support, systems transport
system report » system reform, system support, system reforms
health dence » health device, health science, health devices

Try widening your search to All Fields.

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: (("((health dence) or (health evidence)) network synthesis report") OR ("((health dence) or (health evidence)) network ((((systems report) OR (system report))) or (systems recent))")).
• Removing quotes may allow a broader search: (( ((health dence) or (health evidence)) network synthesis report ) or ( ((health dence) or (health evidence)) network ((((systems report) OR (system report))) or (systems recent)) )).
• Adding a wildcard symbol may retrieve word variants: (("((health dence) or (health evidence)) network synthesis report") or ("((health dence) or (health evidence)) network ((((systems report) OR (system report))) or (systems recent))"))*.