陳淑蘭大叫:-冇大冇细=You know big no ?

No, dear,

『 冇大冇细 』means to say, “You don't know how to respect the elders.” in Cantonese.

For example：When you shouted to your grandfather and said, " Go away from my room right now! You're a **x＠#**.” = 『 你不懂得分尊卑長幼, 又＝ 冇大冇细 』

You don't know how to show proper respect
(behave properly)
for elders.