Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban hang » ngan hang
hieu van » hieu va, thien van, lieu va
dai hoi » dai hoc, dai hai, dai moi
mai hoi » mai khoi, lai hoi, mai doi
sach ty » sach y, sach tu, sach thu
van cac » van hac, van cau, van bac
cac xuc » cam xuc, cac nuoc, chat xuc
va danh » va dinh, va dan, va hanh
ty nang » ky nang, ty xang, ty hang
vai cua » dai cua, hai cua, lai cua
tu sach » thu sach, su sach, te sach

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 ty nang ((mai hoi) OR (dai hoi)). hieu van cac xuc ((va danh) or (ban hang)) vai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((mai hoi) OR (dai hoi)). hieu van cac xuc ((va danh) OR (ban hang)) vai cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang ((mai hoi) OR (dai hoi)). hieu van cac xuc ((va danh) or (ban hang)) vai cua triet*".