Like that, so: như vậy / như thế

Như vậy means "like that" or "that way". It goes after the verb and points back to something just said or done: Em đừng nói như vậy. Don't talk like that. Làm như vậy là đúng rồi. Doing it that way is right. In Hà Nội it's như thế.

After nghĩ (think) or nói (say), it means "so": Em cũng nghĩ như vậy. I think so too. Ai nói như vậy? Who said so?

After an adjective, it means "so" or "that much", often with surprise: Sao hôm nay đông như vậy? Why is it so crowded today? Đến in front makes it stronger: xa đến như vậy, that far.

In everyday Saigon speech như is often dropped, leaving just vậy: Đừng nói vậy. Em cũng nghĩ vậy. Both are normal.

At the start of a sentence, như vậy sums up, "so, that means": Như vậy là mình trễ rồi. So we're late, then.

You know cũng vậy for "me too". Như vậy is the full "like that", and như thế nào? (how?) is built from the same words.