In Tang, he learned not only Confucianism, but also astronomy, music and military science, and brought back "Tokan Kanki" (historical records of Eastern Han Dynasty) to Japan, and offered to the Imperial Court many other books and materials, including Keisho (Confucianism documents [130 volumes of "Torai"]), an astronomical calendar book (one volume of "Taien Calendar" and 12 volumes of "Daienreki Ryusei"), a sun clock (Sokuei Kaneshaku), music instruments (Dorikkan, 鉄如方響, 写律管声12条), music theory books (ten volumes of "Gakusho Yoroku"), bows (arms) (絃纏漆角弓、馬上飲水漆角弓、露面漆四節角弓各1張) and arrows (20 of Shakosen [square arrow] and 10 of Heishasen [flat arrow]).
唐では儒学のほか、天文学や音楽、兵学などを学び、帰朝時には、経書（『唐礼』130巻）、天文暦書（『大衍暦経』1巻、『大衍暦立成』12巻）、日時計（測影鉄尺）、楽器（銅律管、鉄如方響、写律管声12条）、音楽書（『楽書要録』10巻）、弓(武器)（絃纏漆角弓、馬上飲水漆角弓、露面漆四節角弓各1張）、矢（射甲箭20隻、平射箭10隻）などを献上し、『東漢観記』を持ち来たらした。