Two Malaysian navy officers aboard the search ship, Azmi Rosedee and Adbul Halim Ahmad Nordin, said they were “doing their utmost” in the face of bad weather and tricky underwater terrain.
Their comments come on the fourth anniversary of the plane’s disappearance.
Flight MH370, carrying 239 people onboard, became one of the world’s greatest aviation mysteries when it disappeared on its way from Kuala Lumpur to Beijing on March 8, 2014.
A renewed search for the plane began in January this year with US-based company Ocean Infinity being hired by the Malaysian government.
This search follows a failed three year mission coordinated by Australia which was called off in 2017 which cost £112m.
The navy officers said: “It’s been more than 30 days now, but the search team remains optimistic. We are giving our utmost to find the plane.
“We have gone through a number of rough days.
“Operations continue even when the sea is rough … but it makes it difficult for us to deploy and recover the AUVs [search vehicles]. This slows us down.
“Aside from that, the seabed of the search areas is hilly and uneven. This also disrupts the AUV’s capability to thoroughly sweep the areas”.
Several pieces of aircraft debris have been found on Indian Ocean islands and along Africa’s east coast, and efforts to retrieve more are ongoing.
Three wing fragments were confirmed as coming from the missing plane, while other pieces, including some cabin interior items, were determined to be “almost certain” from MH370, the investigators said.
Malaysian investigators told Reuters: “In the event that the aircraft is found, the team will conduct further investigation.”
Malaysia’s Prime Minister Najib Razak reiterated the country’s commitment to finding the plane.
He tweeted yesterday: ”We are pushing the global aviation community to take measures to make our skies safer.”
Seabed Constructor, the search vessel, has already searched 16,000 sq km of the 25,000 sq km priority area identified by the Malaysian government.
Officials believe there is an 85 percent chance of finding the plane within the area.
If the search is unsuccessful, Ocean Infinity will expand the search area to 48,000 sq km.
Malaysia agreed in January to pay the firm up to £50 million if it finds the plane.
The contract allows the company 90 days to locate the plane – the time period allows for refuelling time in Australia – meaning the search should end by mid-June.
Mr Azharuddin said on Saturday: “The whole world, including the next of kin, have [new] hope to find the plane for closure.
“For the aviation world, we want to know what exactly happened to the plane.”