Ka dib markii uu matalayay Czech Republic dhowr qaybood oo dhalinyaro ah, Souček wuxuu u saftay kooxda ugu weyn 15 Noofambar 2016 kulan saaxiibtinimo oo ka dhan ah Denmark. Waxa uu sameeyay kulankiisii ugu horeeyay ee tartanka 10kii Juun 2017, kulankii Czech Republic 1<unk>1 ee ay Norway ka horjeedeen ee isreebreebka Koobka Adduunka 2018. Souček wuxuu ka soo muuqday dhammaan seddexda kulan ee Czech Republic ee ka hooseeya 21 ciyaaryahan ee 2017 UEFA Under-21 Championship.