Complex sentence: Repair and improvements were undertaken in 1703 and 1758, during the Joseon dynasty, however the Confucian-oriented rulers tended to suppress Buddhism and the remote mountain grotto was seriously damaged by the turn of the 20th century.
Split into simpler sentences: Repair and improvements were undertaken in 1703 and 1758, during the Joseon dynasty. However, Confucian-oriented rulers suppressed Buddhism, and the remote mountain grotto was seriously damaged by the turn of the 20th century.