Pari gbolohun ti o tẹle: Bućan ṣe ikẹkọ awọn ayanfẹ ọdọ ọdọ ti ẹgbẹ orilẹ-ede Serbia (labẹ-18, labẹ-19, labẹ-20). Ni 2013 FIBA Europe Under-18 Championship, Serbia pari 6th laarin awọn ẹgbẹ 16. Ní 2014 FIBA Europe Under-18 Championship Serbia gba àmì ẹ̀yẹ fàdákà. Níbi tí
2015 FIBA Under-19 World Championship, Serbia pari 9th laarin awọn ẹgbẹ 16. Ni 2016 FIBA Europe Under-20 Championship, Serbia pari 11th laarin awọn ẹgbẹ 16.