Where to get Crest Teeth whitening in Yichang?

And how to tell the shop keeper about it in Chinese?
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Crest teeth whitening toothpaste is available in every supermarket in China that I've ever visited. The toothpaste is clearly marked Crest in English. To get the whitening version ask for ??????? pi?o bái yá ch? de yá g?o or ??????? jié bái yá ch? de yá g?o In a self service place just look for ?? on the tube. It means white teeth.
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