yes friend
i know there's fake like thailand quality grade AAA
but i wanted to know the shop in where
some one indonesia people say it in Alor setar malaysia hhehehe
if you know where's the store , please tell me ya the contact person
indonesia people say in alor setar but i dont find in googling heheheh 
and for the other if know the contact supplier who sell retro/vintage soccer jersey not original/fake like thailand quality just tell to me ya .. i'm hunting

hmmm.. i don't think it is dirt. From what I see, it's more like the gold colour getting oxidised and thus it looks dirty and not shiny.. if that's the case I don't think there's a way to reverse the effect. Maybe the gold NN is juz not meant to be washed. Washing is usually the reason of the Gold being oxidised, therefore, the more u wear, the more u wash, the worse it gets. not juz by washing, even constant exposure will make it look like that. juz like how some of our gold jewellery loses some it's shine after a long time.

juz my point of view though, hopefully the otai's will correct me if am wrong and shed more light on this matter.

That is quite common for gold nameset. I had the same problem for my germany away OZIL 8 world cup 2010 kit as well. Nothing you can do to fix it.