i found" how to set mi band 4 read thai langauge" in Miband thailand group
1 download app Mi band master from play store
2. in menu wristband change language to spanish (someband must change to french)
3. Finish , your band can read noti thai language
Another language you can try by...
i found this pic in group " miband thailand "
owner that band was comment
" it can read thai language from since unbox. may be it not pass QC from factory"
if this pic is Real
i think officer in factory may be install wrong firmware to this band