Multicultural here? I think that only Tom's comment is close to Cherry's answer, yet we can't satisfy her! I think she means "yet" which acts a bit like "nevertheless": -- She's poor, yet honest → Even if she's poor, she's (anyway/ still) honest. *But is more generic.

In a situation where you connect two sentences which show some contrast, you can use both. But usually "but" suits everywhere. "Yet" sounds like making the contrast more obvious. You can use it in place of "however" for example. And there is a different meaning of "yet" which is "up until now" and you use it in negative sentences in the end. That is its usual meaning. Eg: I haven't done it yet. = I have not done it up until now.

Yet is used in negative sentences and questions to talk about the things that has not happened but that you expect to happen: I haven’t seen that movie yet. But is used to express contrast between opposite true: She is tall, but her sister is shorter. My English is not so good, but I hope to improve soon!

Do you mean something like this? - The lions had not eaten for days, and yet they didn’t attack the tourists Vs - The lions had not eaten for days, but still, they didn’t attack the tourists ?