'Please, someone with English as mother tongue to transcribe what they sing... '

Hello, Roberto. I understand your problem! If you are speaking of the YouTube video that masato linked above, it is far from clear. Much of the time they are singing 'la la' or perhaps 'da da.' When they sang English, there were many words I couldn't understand.

If you can listen to the singing while looking at the words listed here, perhaps you find the correlation.