Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh dai » hanh tai, hanh dao, vanh dai
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, mang may
hieu va » lieu va, hieu qua
cau luc » cau truc, cau phuc
luc van » luoc van, luu van, duc van
va cau » van cau, va cac, va dau
cua tu » cua tuc, cua su, cua cu

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 y ((nang ma) OR (nang cao)) hoi. hieu va cau luc van hanh dai cua tu~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang ma) OR (nang cao)) hoi. hieu va cau luc van hanh dai cua tu".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang ma) OR (nang cao)) hoi. hieu va cau luc van hanh dai cua tu*.