The Titles of Magical Books in Harry Potter

A Guide to Medieval Sorcery

Simplified Chinese (Mandarin: China)
中世纪巫术指南 Zhōng-shìjì wūshù zhǐnán	中世纪 zhōng-shìjì = 'middle' + 'century' = 'middle ages'. 巫术 wūshù = 'wizardry'. 指南 zhǐnán = 'guide'.	Guide to Medieval Wizardry
Traditional Chinese (Mandarin: Taiwan)
中世紀魔法指南 Zhōng-shìjì mófǎ zhǐnán	中世紀 zhōng-shìjì = 'middle' + 'century' = 'middle ages'. 魔法 mófǎ = 'magic'. 指南 zhǐnán = 'guide'.	Guide to Medieval Magic
Japanese
中世の魔術ガイドブック Chūsei no majutsu gaidobukku	中世 chūsei = 'middle era' の no = connecting particle 魔術 majutsu = 'magic' ガイドブック gaidobukku = 'guidebook' (from English).	Medieval Magic Guidebook
Vietnamese (Chinese characters show etymology)
Hướng Dẫn Về Ma Thuật Thời Trung Cổ	hướng dẫn (嚮引) = 'guide'. về = 'concerning'. ma thuật (魔術) = 'magic, sorcery'. thời (時) = 'time'. trung cổ (中古) = 'middle' + 'old' = 'medieval'.	Guide to Medieval Magic
Mongolian (new)
Дундад зууны үеийн ид шидийн гарын авлага Dundad zuunii üiin id shidiin gariin avlag		Handbook of Middle Century Period Magic

Sorcery:

The Chinese translator uses 巫术wūshù ('wizard arts') as the term for 'sorcery'.

The Taiwanese translator prefers 魔法 mófǎ ('magic').

The Vietnamese and Japanese translators use 魔術 majutsu or ma thuật (= 魔術), meaning 'magic arts' or 'magic skills'. This is slightly different from the meaning in Chinese, where 魔術 / 魔术 móshù refers to magic tricks or conjuring tricks (à la David Copperfield).

Medieval:

Historical periods are a perennial source of confusion. The Medieval era or Middle Ages is the period of European history between the fall of Classical civilisation (the Roman Empire) and the rediscovery of ancient learning in the Renaissance. It is normally equated to feudal society. The exact boundaries of the Medieval period vary from historian to historian. (Look here for a scholarly debate on the definition of 'Medieval').

For 'medieval' in the European sense, Chinese normally uses 中世紀 / 中世纪 zhōng-shìjì, quite literally the 'middle centuries'. Alternative names are 中世 zhōngshì ('middle era') or 中古 zhōnggǔ ('middle antiquity').

Japanese generally prefers to call the European Medieval period 中世 chūsei ('middle era'), as in the translated title of this book.

Although Vietnamese also has the term trung thễ kỷ equivalent to 中世紀, the more common term for the European Medieval period is trung cổ (中古) 'middle antiquity', which is used by the translator of Harry Potter.

(Terminology is somewhat different in non-European history. In Chinese history, 中古 zhōnggǔ tends to be used for the period from 3rd to 9th centuries, regarded by some as the Chinese 'Middle Ages'. This is then followed by the Chinese 中世紀 zhōng-shìjì. However, historical classifications vary widely.

In Japanese history, the term 中古 chūko 'middle antiquity' in a literary context specifically refers to the pre-feudal Heian Period from the 9th-12th centuries.)