I tried some Husten- und Bronchialtee recently when I had a cold, but it didn’t seem to help, perhaps because I didn’t believe in it enough. Tee (tea) has a wide meaning in German and most of these teas sound like the condition they are supposed to avert. As one of the tweets quoted by Bettina says, Blasentee (bladder tea, diuretic tea) is not the same as bubble tea.