Malaysia to identify suspected debris in Maldives

Jian said it's not an easy job to find enough wreckage in the Indian Ocean, a vast area with wild gales and complicated ocean currents.

Besides, there are only two inhabited archipelagos between the western Australian shore and La Reunion, making it especially difficult to spot debris from other islands.

Jian suggested the Australian-led search team continue combing over a 120,000-square-kilometer search zone, which was confirmed through satellite data to pinpoint the plane's path.

The search for the black box is still the core objective, as the data within it is key to solving all the mysteries, said Graham Braithwaite, an aviation security expert at Britain's Cranfield University.

But as the batteries had run out, the black box was not sending anymore signals, making the underwater search "blind."

David Gallo, who co-led the search for Air France Flight 447 that crashed in the Atlantic Ocean in 2009, said it's most likely that the black box lies somewhere on the sea floor.

Compared to a surface search, an underwater search takes longer and needs much more luck, said Gallo, who now works as director at the U.S. Woods Hole Oceanographic Institution.

Since 1965, black boxes from 19 crashed planes have not been found yet, including that of MH370.

The black box, which records flight data and cockpit voice, could sustain explosions and seawater. It's believed that the black box is virtually indestructible and would help analyze the causes of air accidents.

Still, further clues might emerge from the wreckage found on La Reunion. Gallo said that barnacles attached to the debris are important clues to finding the ill-fated plane.

The size of barnacles, crustaceans that live stuck to hard surfaces under sunlight, could tell how long the debris had been in the water.

Scientists could also analyze which part of the ocean the debris came from through the species of barnacles as chemicals inside the barnacles could vary in different waters.