Police will begin trawling through CCTV footage from up to 100 Hamilton bars as the search for missing Auckland woman Carmen Thomas intensifies.

A land search yesterday with two cadaver dogs - trained to sniff out decomposing bodies - of the Orakei Basin behind the 32-year-old's Remuera home failed to find anything.

Ms Thomas, a South African native who was working as an escort in Pakuranga, was last seen in Auckland on July 1 and her black Nissan Pulsar found on Hamilton's Dyer Rd four days later. She was reported missing last Tuesday.

Detective Inspector Mark Benefield said there was nothing to indicate Ms Thomas had gone to Hamilton but police would look at footage from bars to try to "narrow down the timeframe" of when she went missing.

"They tell me that there are 100 bars in Hamilton ... some of them lose their video footage quicker than others. It's just a matter of looking through them."

Mr Benefield said police would consider searching the Waikato River, "If something pointed us in that direction, obviously it's a big river".

Two dogs and a search-and-rescue team spent most of yesterday searching the Orakei Basin and the Kepa Bush Reserve behind Ms Thomas' Ngapipi Rd home.

Mr Benefield said the longer Ms Thomas was missing, the more police "had to be realistic".

"We're looking at the logical places ... to make sure that we haven't missed something.

"If we're using search and rescue ... and we used two cadaver dogs, we're looking for a deceased.

"The only reason we are doing that is it's logical for people, usually nearby home, to get lost, break an ankle ... going for a walk with their dog but [have] fallen down a bank. It could be any myriad of reasons as to [how] they've come to their demise."

Unconfirmed sightings of her since July 1 had been eliminated, Mr Benefield said.

Police are also collecting CCTV footage from businesses in Auckland. Footage released yesterday shows Ms Thomas entering the Newmarket Day Night Pharmacy on Broadway on June 25 shortly after 6pm, wearing a black, long-sleeved top, a grey skirt, black boots and a purple scarf. She walks through the doors, and leaves about a minute later with a purchase.

Footage two days later shows her at the Greenlane Countdown at 7.10pm, wearing a beige-coloured jacket and the same purple scarf with her hair pulled back - the same day her bank account was last touched.

Ms Thomas' mother, Teresa Scott, is expected to arrive in New Zealand on Friday.

* Anyone with information about Carmen or her car should contact police on 0800 537 735 or on whereiscarmen@police.govt.nz. Anonymous callers can phone Crimestoppers on 0800 555 111.