Perhaps you should try some spelling variations:
incidence networks » inference networks, science networks, incidents network
influence networks » inference networks, inference network, reference networks
health guidance » health evidence, health finance, health substance

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 ((incidence networks) OR (influence networks)) synthesis report ) OR ( health guidance ((network synthesis) OR (network systems)) report )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( health ((incidence networks) or (influence networks)) synthesis report ) or ( health guidance ((network synthesis) OR (network systems)) report ))".
• Adding a wildcard symbol may retrieve word variants: (( health ((incidence networks) or (influence networks)) synthesis report ) or ( health guidance ((network synthesis) OR (network systems)) report ))*.