this thing is called bai-bao-jia.The Chinese used it to store flat items about a hundred years ago.
I tried looking up ābai-bao-jiaā, and also the words āzhen xian baoā which I later found associated with it, but I only got pictures of bao buns. So after searching for various iterations of āChinese paper pocket storageā and so on, what you want to google in English is āChinese thread bookā to find lots of pictures, variations and tutorials.
Edit: to clarify, the reason I couldnāt find it with those search terms is cos the Google algorithm is shit now. As I understand it, those are the real (transliterated) names.



















