You may need an embassy visa for Bosnia and Herzegovina if you have a Nauruan passport
Visa options for Bosnia and Herzegovina (2)
You don't need a visa. You can travel to your destination for a limited stay. Be sure to check other entry requirements and how long you can stay for.
Visitor visa
Travellers need a visa to visit Bosnia and Herzegovina for Business or Tourism. A paper or embassy visa is the only visa available for travellers visiting Bosnia and Herzegovina. The visa is typically a stamp or sticker added to the passport. Travellers must obtain this visa from a local embassy, consulate or visa center before travelling.
This is not offered by sherpa°.
Apply on the government site.