Chinese characters not displayed properly in firefox ?

I use Arch -Linux linux distribution, I don't speak chinese , but I surf some chinese trackers from time to time , the problem is the characters are not displayed properly as you can see in this screenshot

so, how can we fix it?
just install this package .. which is basically a sans-serif font with all chinese glyphs 
sudo pacman -S wqy-microhei

that's it.