Aliexpress
Click here… to search for Xiaomi 70mai Portable Wireless Car Vacuum Cleaner on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (79.51 USD): BGCarEle4
Coupon (85.12 USD): Cuponation9
Coupon (87.93 USD): BG00c906
(CouponsFromChina.com tip: put item in your cart and apply coupon code there 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): BGAutos, BG70MAI18, BGCARELEC, BG70maiCleaner, BGAFF10OFF, BGCuponation10, 13f142, BGHONEY2110, BG10OFFAFF, BGwhielabel, BG10OFFAFF1, BANGGOODSD, 00c906, ADMITAD2212, 2022ACTIESNL, BGCarEle1, MVC8SPRING, 8BGwbg2204, BGCarEle3, BGAUTO22, BGdcbfa8, DealBGimpact
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi 70mai Portable Wireless Car Vacuum Cleaner.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).