Perhaps you should try some spelling variations:
cac triet » cac thiet, cac trieu, cau triet
sach tay » xach tay, sach hay, sach nay
tay lang » tai lang, tay tang, tay quang
hanh vai » hanh vi, hanh va, hanh tai
vai cac » va cac, tai cac, voi cac
va hanh » van hanh, va thanh, va danh
ve cham » va cham, ve chat, vu cham
tu sach » thu sach, su sach, te sach
dai hoi » dai hoc, dai hai, dai moi
mai hoi » mai khoi, lai hoi, mai doi
tuc va » thuc va, truc va, tuc xa
ve cac » va cac, vien cac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach tay lang ((mai hoi) or (dai hoi)). hieu ((ve cac) or (ve cham)) tuc va hanh vai cac triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tay lang ((mai hoi) OR (dai hoi)). hieu ((ve cac) OR (ve cham)) tuc va hanh vai cac triet.
• Adding a wildcard symbol may retrieve word variants: tu sach tay lang ((mai hoi) or (dai hoi)). hieu ((ve cac) or (ve cham)) tuc va hanh vai cac triet*.