Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cham tuc » nham thuc, pham thuc, tham thuc
va dinh » van dinh, va kinh, va tinh
va danh » va dan, va hanh, dia danh
vu cham » va cham, vu kham, tu cham
sach ty » sach y, sach tu, sach thu
hieu vu » hieu va, hieu ve, hieu su
cao hoi » co hoi, cao hoc, tao hoi
vai va » mai va, dai va, hai va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty xang ((cao hoi) or (cau hoi)). hieu vu cham tuc ((va danh) OR (va dinh)) vai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty xang ((cao hoi) OR (cau hoi)). hieu vu cham tuc ((va danh) OR (va dinh)) vai va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty xang ((cao hoi) or (cau hoi)). hieu vu cham tuc ((va danh) OR (va dinh)) vai va thiet".
• Adding a wildcard symbol may retrieve word variants: thu sach ty xang ((cao hoi) or (cau hoi)). hieu vu cham tuc ((va danh) OR (va dinh)) vai va thiet*.