Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (26.99 USD): bgshOOp10
Coupon (26.99 USD): bGhOnEy10
Coupon (26.99 USD): BGHome15%
Coupon (26.99 USD): BgcLuBofErtA10
Coupon (26.99 USD): BGTEXTILE
(CouponsFromChina.com tip: this code has to be applied 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): HP920, XMT920, XMID109, 15HTR, 502C6B, vipupgrade8, TTxBG10, BGDEER05, aff7off, BGss8%hl, bgssaff9, AFfbG10, BGMDW20, BGDeer7, BGHOMEG12, FBCOUPON1, BGHOMEA15%
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Deerma Clothes Sticky Hair Trimmer.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).