"Once the sea was difficult for water, it was always amber." The meaning of this sentence: people who have experienced the incomparably deep and wide sea will find it difficult to attract him by the water elsewhere; Except for the clouds steaming in Wushan, the clouds in other places are eclipsed.
Once: experienced. Zeng, adverb. Experience.
Bohai Sea: The ancients generally called Bohai Sea Bohai Sea.
Except: except.
It means: Qian Jie can't compare with anyone in my heart.