Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
dinh ve » dinh ket, dinh van
dinh cu » dinh cuu, dinh chuc, dinh chau
cau luc » cau truc, cau phuc
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
luc va » duc va, tuc va, loc va
va cau » van cau, va cac, va dau
5 hoi » o hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach tru nang ((5 hoi) or (xa hoi)). hieu va cau luc va ((dinh cu) or (dinh ve)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tru nang ((5 hoi) OR (xa hoi)). hieu va cau luc va ((dinh cu) OR (dinh ve)) va triet.
• Adding a wildcard symbol may retrieve word variants: su sach tru nang ((5 hoi) or (xa hoi)). hieu va cau luc va ((dinh cu) or (dinh ve)) va triet*.