An extensive and exhaustive effort including a deep ocean search found no sign of the air craft.

经过广泛而彻底的努力，包括深海搜索，没有发现任何飞机的迹象。

Both are warning the deep water search could take anywhere from 8 to 12-months.

双方均警告称，深海搜寻工作可能持续8至12个月的时间。