Perhaps you should try some spelling variations:
health impedance » health importance, health temperance, head impedance
health science » health sciences
systems report » system report, systems support, systems recent
health device » health service, health services
health dence » health devices, health degree, health danger

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 evidence) OR (health science)) network synthesis report ) OR ( ((health dence) OR (health device)) network synthesis report ))) OR ( health impedance network systems report )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( ((health evidence) OR (health science)) network synthesis report ) or ( ((health dence) or (health device)) network synthesis report ))) or ( health impedance network systems report ))".
• Adding a wildcard symbol may retrieve word variants: (((( ((health evidence) OR (health science)) network synthesis report ) or ( ((health dence) or (health device)) network synthesis report ))) or ( health impedance network systems report ))*.