There is indeed vegetable glycerin in Hong Kong e-cigarettes.
In Hong Kong, e-cigarettes are often referred to as "electronic atomizers" or "vapour atomizers", and the liquids used mainly contain vegetable glycerin, propylene glycol, nicotine and other additives.
These e-liquids are usually available through vaping shops, tobacco markets or online.
However, it is important to note that not all e-liquids are the same, and different brands and models may have different ingredients and qualities, so it is important to choose a reliable brand and product.
Hong Kong implements a ban on smoking, so you must also understand the relevant policies.