Your former partner relocated with your child in another country without your consent?
Do something and now!
You were living in a country and the other parent moved with your child without your consent or a court decision? The other parent went on vacation with the child and never came back? This is most certainly an unlawful abduction or detention.
It will often be possible to apply the 1980 Hague Convention.
Consult your lawyer specializing in International Family Law immediately.