Basically copy coupon, view price history or create e-mail price alert. You probably want to know what is the best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Charging Port (Charging Case): USB-C, Capacity (Case): 600mAh B, Bluetooth Profile: HFP/A2DP/HSP/AVRCP, , Case Input: 5V 500mA, Life (with Case): 20h Charging Time, Wireless Range: 10M, Bluetooth Version: 5.0, Brand: Xiaomi, attery Type: Li-ion, Capacity (Earbud): 46mAh, Control Type: Multi-function Button
Banggood
Banggood warehouse is located in Hong Kong.
Link: Banggood product page
1. ($14.99): BG6f9aca
2. ($15.99): BG997bf8
paste coupon code in your cart and click Apply after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGXM2SA, BGML2S, BG4BW25, BGXM2SB, BG2SAA, BGLOAC1, 13f142, BGRM2S27, BG6b2bc5, BGfae052, BG53ac8b, BG7edcdc, BGc77463, BG7HM2S, BGdfb04e, BG468935, BG0247c4, BG73b78e, BG018df6, 6GSGIT
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for Xiaomi Mi True Wireless Earbuds Basic 2S? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).