Police investigators have searched the home again, using a camera to look inside a water tank.
"We'll just keep going, looking, searching every nook and cranny - no stone unturned." Commissioner Webb told Nine Network.
Detectives and emergency services returned to the home on NSW's mid north coast last week, and have now shifted to nearby sites.
Divers searched a creek about a kilometre away from the house on Benaroon Drive, while also digging up land with an excavator to ensure all areas have been checked.
"It's been seven years now and that's a long time, but we're not going to give up. I'm confident this team will just keep pursuing this until we get a result."
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