In Chinese, verbs can be reduplicated. The form for reduplicated monosyllabic verbs is "AA' or " A-A". However, the form for reduplicated bisyllabic verbs is "ABAB", and "一“cannot be added between the two syllables of bisyllabic verbs. For example: 看看， 说说，等一等，数一数，介绍介绍，etc. Reduplicating a verb has the function of implying a short duration for that action or the idea of giving something a try. In this sense, it is similar to adding"一下“ to the verb. --(From NPCR 2)

不妨參考 我的回答 漢語 動詞 重疊 形式 http://www.italki.com/question/149073?answer-sorting=2 香香你的嘴 香 通常 做 形容詞用 這裡 用作 使動動詞 意指 使你的嘴巴香香的 也就 適用以上 動詞重疊形式 的用法

It is just a spoken language, and advertising expression. It means that this kind of snacks is yummy. Thx.

it's one word consisting of two symbols

Just spoken language。Advertising Creative.广告创意，有的词句并非原先的意思。