Esther Wallace was last seen early Wednesday. A companion said they were separated while hiking at Federal Falls about one kilometre south-west of Mount Canobolas.

At least one item of clothing was recovered by SES and ambulance workers over the weekend, the Central Western Daily understands.

The discovery is believed to have extended the search - now in its sixth day - and narrowed down an area of interest.

It's unclear what type of clothing was found. Searchers are reportedly operating on the belief it may have been owned by Wallace.

A spokesperson for NSW Police said: "A large number of items have been found in the area, however, none are confirmed to be relevant to the investigation."

The spokesperson once again declined to say if a criminal investigation is underway. On Sunday police said: "There will be no further comment."

Last week police told the Central Western Daily they were "keeping an open mind" in the search. No further updates were available at that time.

Five NSW Police units, the SES, RFS, and staff from Cabonne Council, NSW Parks and Wildlife Service, and Forestry NSW have trawled the circa-14-square-kilometre reserve since the woman's disappearance.

Searching has generally run from about 8am to 7pm. Some smaller patrols have run through the night.

The Central Western Daily understands dog and aerial search teams from Sydney had been on standby over the weekend but were not used.

Helicopters could be heard overhead in the State Recreation Area on Friday evening. Fire trails and access roads have been severely damaged by heavy recent rain.

Officers from Central West Police District, the Police Rescue and Bomb Disposal Unit, PolAir, Chifley Rural Crime Investigators have contributed to the search.

A spokesperson for the SES said on Thursday: "A good rule of thumb is 48 hours at this time of year, you really want to be finding something."

Esther Wallace is 47 years old and of Caucasian appearance with blonde hair. Police believe she was wearing an orange jacket, black pants, and sandals at the time of her disappearance.

Anyone with information on the woman's whereabouts are urged to contact Orange Police Station or Crime Stoppers 1800 333 000.

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