Aliexpress
There’re some similar items on Aliexpress in my database. There may be some other items though.
More on Aliexpress…Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. I couldn’t find any coupon for this product on latest product update.
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): 502C6B, 0c6c20, vipupgrade8, TTxBG10, BGMICLOCK, BGPMIBT45, AFfbG10, BG25GAGA, BGBT046, BGMIJIAT1, BGXM134, BGBT4PL, BGBT408, BGMIJIAT, BGMIT12, BGBT40PL, BGLAO12, BGEOFH22, BGWEO12, BGMIE88, BGBINKUPON760, BG12CLK, BGBFCR01, BGBT4RA, BGMIJ119, BGMTCK, BGMJ1188, BGXT1177, BGBAPOHG, BGVDay10%off, BGTFKD, BGHOMEG12, BGMIJIAT13, FBCOUPON1, BGma685, BGTT10, BGxm485, bGhOnEy10, BGBT40RA, BGCNMIJIA1, BGKS453M, BGCNXiaomiJuly1, BGdragonBoat, BGVVDCB, BGSS10%SW, BGLKZZVVDC12, BG760VV, BGXMST760, BGXMYB760, bgshOOp10, BGDQHOME28, BGHome15%, BGGFHOME27, BGCZPROHOME, BgoFErTaSchInA10, BGCZOC760, BGHOMEA15%, BGCODEYR760, BGELEHOME44, BGMS760, BGCODEYB760, BgcLuBofErtA10, BGBFHOME33, BGLD2A56, BGDESE760, BGAFF10OFF, BGFEFR760, BGFEFO760, BGMARFR760, BGMASE760, BGCuponation10, BGMRDC50, BGXIAOMI760, BGMAFO760, BGAPXIAOMI4, BGAPFO760, BGMAYFR760, BGwhielabel, BGMIGLA20, BGJUSE760, BGMIGULS, 13f142, BG10OFFAFF1, BG02a279, 6GSGIT, BG1142b6, BGe7a612, BG21c1cf, BG152352, BG4a7a54, BGb018c9, BGce5aee, BG110096, BGc4a05f
(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 Mijia Bluetooth Smart Hygrometer Thermometer.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).