Perhaps you should try some spelling variations:
tai khoa » da khoa, noi khoa
hanh dai » hanh tai, hanh dao, vanh dai
van hanh » van thanh, ban hanh, van anh
van nang » van quang, van ban, van dong
luc van » luoc van, luu van, duc van
cau luc » cau truc, cau phuc
hieu ve » hieu va, hieu van
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
tai hoa » thai hoa, thi hoa, dai hoa
ve cau » ke cau, va cau, ve cac
v nang » va nang, vu nang, voi nang

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

• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((v nang) OR (van nang)) ((tai hoa) OR (tai khoa)). hieu ve cau luc van hanh dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((v nang) or (van nang)) ((tai hoa) OR (tai khoa)). hieu ve cau luc van hanh dai cua tre~".
• Adding a wildcard symbol may retrieve word variants: so sach ((v nang) or (van nang)) ((tai hoa) OR (tai khoa)). hieu ve cau luc van hanh dai cua tre*.