Deputy Prime Minister Trinh Dinh Dung said in a statement, “We can estimate the path of the storm or the amount of rain, but cannot predict when landslides may occur.”
“The road is covered under deep mud and heavy rains are still luring the area, but rescue operations have to be done quickly.”
Since early October, Vietnam has been affected by hurricanes, heavy rains and floods, affecting more than a million people.
The government said that Typhoon Molway – also known as Quinta – left millions without power and damaged 56,000 homes.
Twenty-six fishermen also went missing after drowning in an attempt to return to shore on Tuesday.
Molev has weakened into a tropical depression after making landfall on Wednesday and is expected to reach Laos later on Thursday.
The Meteorological Agency of Vietnam said that up to 700 mm (27.5 in) of heavy rain will continue in parts of Central Vietnam until Saturday.