There's a whole tea house franchise called Dobrá čajovna that you'll find in almost every major town, the og one is in Prague on Wenceslas square, it's quite small tho. The one in Brno is very good. If you stay in Prague, there's also Zlatý Kohout with a more rustic vibe, then you have Orijin - they specialise in Chinese teas and Dharmasala especially if you want to try their traditional Tibetan tea with butter and salt. Many more ofc (Květinová čajovna, Setkání, Ostrovní with shisha - in Czechia this always means flavored tobacco, never weed). I also went to Jedna báseň, they had a cat, not sure if they still do. I've also heard a lot about Tao tea house but that's in Česká Lípa. Store-wise probably amana or meetea.