Police and search and rescue teams are combing farmland on the outskirts of Christchurch, looking for items of interest in the search for Yanfei Bao.
The 44-year-old real estate agent was last seen in the suburb of Hornby on 19 July and police are now treating her disappearance as a homicide investigation.
Detective Inspector Nicola Reeves told RNZ police were continuing to look for Bao and any items found during the search were being assessed for a connection to the case.
Greenpark remained a key part of the search area, she said.
Specialist teams were doing a thorough search of a number of paddocks and tree lines for the next day or two, she said.
A 52-year-old man has been arrested and has appeared in court on a kidnapping charge.