Natasha Narang, a PhD student at the University of Tasmania, was last seen on October 4 at Mowbray in the state.
On Thursday, police search and rescue officers scoured the Tamar River in Tasmania after discovering some items belonging to her on its banks.
However, the search, which involved a helicopter, failed to locate Narang.
Narang, who is from Punjab, travelled to Australia to do her PhD on Indians studying in regional Australia, The Examiner reported on Monday. She moved to Tasmania with her husband Sandeep in November 2012.
Police do not suspect any suspicious circumstances in her disappearance on October 4. They believe study related stress may be the reason for her disappearance.
Elders among the Sikh community in Launceston city have said high expectations among international Indian students often leads to stress.
A number of people have come forward to police with information about Ms Narang's whereabouts just prior to her disappearance.
One motorist said she saw Narang crossing the East Tamar Highway near the northern outlet.