The translation for the word "volume" is listed as "âm lượng" when hovering the mouse cursor over it, when it should be "thể tích."
Thể tích (體積) for measuring the volume of liquids.
Âm lượng (音量) for measuring the volume of sounds.
Quyển/cuốn (卷) or tập (集) for volumes of books.
The word "âm lượng" is sound volume. They are homonyms in English.
So in order to introduce a new word you give the wrong definition according to the context of the lesson... Helpful