Investigators have scoured bushland around Darebin Creek in Heidelberg West, Sparkes Reserve in Ivanhoe and Napier Waller Reserve in Alphington today in the hope they would find the 33-year-old's body.

Detective Inspector Andrew Stamper said despite the thorough search of the areas, Ms Zhang was yet to be found.

"Unfortunately we haven't found anything we were looking for, but we will continue," Detective Stamper said

"It's frustrating, we want to be able to provide answers to Ju's family.

"Our key priority is to get answers to Ju's family."

Detective Stamper said it was important to eliminate the areas searched today and the entire area was of interest.

Police are urging the caller to make contact again.

"We're still very keen for that person to call us back," Det Insp Stamper said.

Ms Zhang's family are mostly in China while her eight year old son is in Melbourne.

"With the state of the world at the moment (Ms Zhang's family) not being able to assist would be heartbreaking," Det Insp Stamper said.

Police have made a fresh plea for anyone with CCTV footage from that night around a light industrial area off Waterdale Road in Heidelberg West to contact Crime Stoppers or local police.

Detective Stamper also said anyone who noticed anything suspicious over the past two weeks should also contact authorities.