in the same veinadvadverb: Describes a verb, adjective, adverb, or clause--for example, "come quickly," "very rare," "happening now," "fall down."
(regarding the same subject)
同一个主题的 tóng yí gè zhǔ tí de
同一个调调的 tóng yí gè diào diào de
He started talking about politics and went on and on in the same vein for two whole hours. My sense of humour's in the same vein as yours: we both laugh at the same jokes.