The Vietnamese word "giấy thiếc" refers to "tin foil" or "aluminum foil." It is commonly used to wrap various items, especially food. In the context of tobacco, "giấy thiếc" specifically refers to the tin foil used to wrap cigarettes.
While "giấy thiếc" primarily refers to tin foil, in some contexts, it may also refer to any thin metallic paper used for wrapping or packaging.