[Authentication] Birth-certificate translation/certification

I’m Hans from Holland and started the procedure to live with my Taiwanese girlfriend in Holland.

Does anyone have experience with approval outside Taiwan of the birth certificate which are filled in by hand at the Household registration office?
Or is there a more legal one available if we are persistent at the office?

It appears that you want some official certification of your Taiwan friend’s birth.

All Taiwanese have household registration. It is possible to get an official copy of the household registration document and have it translated into English.

I believe that this would provide the best proof, in terms of what you are looking for. The household registration document will contain full information on the birthdate, ID number, parents names, household address, etc. of the person involved.