Yeah, what does that mean?

An exclamation of admiration or surprise.

Ah, this can be used to express a surprise, a coping method when you don't know how to answer the phone, and this stalk may also express a kind of sympathy, banter or joke.

Ah, this sentence is often used by network anchors in live broadcast, and it is very popular, so more and more netizens begin to use it.

Ah, this can be used to express a surprise. It is a coping method when you don't know how to answer the phone, which means to pause and ease the embarrassment. People who say "Ah, this" are sympathetic/joking/joking to each other.