Aliexpress
Click here… to search for Xiaomi YDLYEJ01LM Wireless Bluetooth 4.1 Sport Earbuds on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Hong Kong.
Link: Banggood product page
Coupon (20.29 USD): e40853
Coupon (24.64 USD): e2bcea
Coupon (24.64 USD): 502C6B
(CouponsFromChina.com tip: paste coupon code in your cart and click Apply after clicking “Proceed to checkout”. Click to copy code and open shop)
Old coupons (from the oldest to the newest): bd9930, 684137, 161d80, 14c42f
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Price history (for all/most countries) for Xiaomi YDLYEJ01LM Wireless Bluetooth 4.1 Sport Earbuds is here.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).