Aliexpress
Click here… to search for Xiaomi YIWUYISHI 6Pcs PPS Glass Fiber Chopsticks on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (17.99 USD): BGAFF10OFF
Coupon (17.99 USD): bGhOnEy10
Coupon (17.99 USD): BGdragonBoat
Coupon (18.59 USD): BGAFF7OFF
(CouponsFromChina.com tip: you should apply the coupon in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): e2bcea, 502C6B, 59c904, vipupgrade8, TTxBG10, aff7off, BG1099chop, 2019SPEDM, bgssaff9, AFfbG10, BG30offchop, BGBFAFF2019, BGCITYADS2019, BGHOMEG12, BGYY25RE, BGSS10%SW, bgshOOp10
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi YIWUYISHI 6Pcs PPS Glass Fiber Chopsticks.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).