buồn
sɯɫphɯdɐ sjuːlpjuːdə təbi sad ɔːɹ ɐ fɹeɪz laɪkmɐɯmi ɐphɯdɐ miːjuːmi eɪpjuːdə tə hav ɐ hɜːtɪŋ hɑːt
In Korean 슬프다 (seulpeuda - to be sad), or a phrase like 마음이 아프다 (maeumi apeuda - to have a hurting heart)
A feeling of sadness, often stemming from loss, disappointment, or loneliness.
Example
"Tôi thấy buồn vì chuyện đó."