The Xiaomi slogan mentioned that it can take into account both macro and telephoto means that the liquid lens can not zoom, but can quickly change the focal length and focus. A very simple example is, your eyes can quickly focus from the object in front of you to the distant scenery, but can it magnify the distant view? The answer is no.
Another digital blogger explained: Xiaomi’s liquid lens is not a new technology in the camera. Canon’s 14-year patent information can be found at hand. In short, liquid lens is a water polo, and the water volume of the water polo is different in different shapes. In the same way, the internal liquid pressure (and possibly other physical properties) can be adjusted by external driving to change the external shape of the lens. The natural refractive index is different for different lens shapes.
In fact, to sum up, the advantage of liquid lenses is that they focus faster and are smaller.
Mike Lee-111 
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Blair