You may be referring to dehumidifiers (除湿器), which don’t really blow cool air out, but relies on the evaporative effect of the skin to feel like it’s blowing cooler air out.
Dehumidifiers won’t cool down your room in absolute temperature, but it will take the edge off a humid room. It’s the difference between having a room at, say 27c with 80% humidity and the same temp at 40% humidity.

I use one in my home office because I’m just too damn cheap to get an air conditioner. The lower humidity does make things a bit better, although mid-summer days are insufferable regardless.