I found it while surfing through a chinese site.
Frankly, I find it AWFUL.
I don't know who sang it or who wrote the lyrics but it simply SUCKS

The voice makes me feel.......uneasy.......
and for the lyrics.......judge them by yourself.....

I've translate it into English.
It's not really good but it's close to the Mandrain version.
I don't think the Mandrain version is GOOD though........
Eason Chan's chinese version is not good already,
but believe me, this is worse.........
Here goes the mp3,
Mandrain Version of MelissaIt's rough so don't expect to hear something in high-quality

and here goes the lyrics:
Fullmetal good brothers
Gives the world hope and light
Care for people in the world
Always in front of danger
They will always be brave
To destroy all the devils
Blue sky
Birds are singing happily in the sky
The sound of recorder floated
Fish are swimming in the sea
But cannot find the end
So have to go on swimming and swimming
Is you who give me bravery
Not afraid but caring and loving
I just want to use my metal arms
To clear all the evil of this world
Create a better future forever peace
Fullmetal good brothers
Gives the world hope and light
Care for people in the world
Always in front of danger
They will always be brave
To destroy all the devils
I don't know how you all find it, but to me, it's CRAP