A Chinese woman allegedly murdered by her teenage housemate might have been dumped in bushland north of Sydney, police believe.
Using phone records, police tracked the movements of Qi Yu's car to areas around Hornsby, Berowra, Cowan and Mt Kuring-gai on the night she went missing.
Ms Yu, 28, was believed to have been transported there in her car, although police would not confirm if she was alive at the time.
Police search teams were scouring the area on Friday and have also asked weekend bushwalkers to look out for evidence.
It is believed Ms Yu's white Toyota Corolla with number plates DLK-13P and green P-plates, was dumped in Burwood in the city's west, around midnight last Friday, police said.
Her housemate Shuo Dong, 19, was arrested on Wednesday after being released from hospital and charged with murder.
Detective Superintendent Kerrie Lewis appealed for anyone who was around those regions on Friday night to try and recall if they saw anything suspicious.
She's also appealing to people in the area this weekend to keep an eye out for women's clothing or bedding, which may help them narrow down the search area.
"Really we would like to appeal to anyone who might be bushwalking in that area over the weekend, mountain biking," she told reporters in Campsie on Friday.
She also appealed for anyone with dashcam footage to contact police.
PolAir, cadaver dogs and police on foot spent Thursday following up leads in areas of bushland but they were fruitless, AAP understands.
The Marine Area Command joined the search on Friday but line searches and dog squads will only be redeployed when stronger leads emerge.
Ms Yu is believed to have gone missing last Friday night from her Campsie home in the city's southwest.
Her friends reported her disappearance on Saturday after they woke to find her missing from her room.
Her car - a white Toyota Corolla with number plates DLK-13P - was found in Burwood, four kilometres from her home, on Saturday.
Dong did not appear in Burwood Local Court on Wednesday and bail was formally refused.
His case is next scheduled for mention in Burwood Local Court on July 9.
Ms Yu's family has arrived in Sydney from China but have been hesitant to make public comments.