In Khmer culture is considered the head of the high. Touching the head or turning the head to the feet, do not polite. Hail to use "Samsung's robust" that resembles the movement of Thailand. Eye contact is considered disrespectful to the elderly.
In Khmer culture regarded as head. Touch the head or feet, facing towards the head, thus not polite. The salutation is used "Sam was all ya" which is similar to the Thai Wai. The eyes with elderly ladies.
In Khmer culture, head of the high-touch his head or face foot to the head, not the polite greeting to use "Samsung เปี๊ยะห์" like the Thai wai. The eyes of the elderly that are not polite