Perhaps you should try some spelling variations:
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
nam tuc » nam thuc, nam truc, nam tu
va hanh » van hanh, va thanh, va danh
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua
de cua » le cua, te cua, dieu cua
x hoi » xa hoi, o hoi, 5 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 ((x hoi) or (x ho)). hieu van nam tuc va hanh ((vi cua) or (de cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tru nang ((x hoi) OR (x ho)). hieu van nam tuc va hanh ((vi cua) OR (de cua)) triet.
• Adding a wildcard symbol may retrieve word variants: su sach tru nang ((x hoi) or (x ho)). hieu van nam tuc va hanh ((vi cua) or (de cua)) triet*.