Divers scoured passenger cabins on the third and fourth floors of the five-story vessel, which sank near Jindo Island off South Korea's southwestern coast Wednesday, Xinhua reported.
The pan-government emergency response centre said in a press release that Coast Guard, military and private divers will be deployed again Monday night and early Tuesday morning to the passenger cabins.
Koh Myung-seok, spokesman of the centre, Monday said that search will pick up speed given favourable weather conditions and guideline ropes.
Five guideline ropes were installed Sunday to enable divers to enter the sunken ferry at a faster pace than before.
Four crew members - two first mates, one second mate and one chief engineer - were arrested Monday, charged with negligence of duty and violation of rescue acts.
The arrests came two days after three crew members, including the captain, were arrested for deserting the ship without making efforts to evacuate passengers.
A total of 22 bodies, four male and 18 female, were retrieved from the passenger cabins during the night-time search and rescue operations.
Among them were two male foreigners.
So far, 87 people have been confirmed dead, but 215 others are still missing. The number of the rescued remained unchanged at 174.
No survivors have been found yet.
The ferry Sewol departed from the western port city of Incheon last week Tuesday night for the southern resort island of Jeju, carrying 476 people, including 325 high school students and 15 teachers, on a four-day field trip.