Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, lieu va, hieu ve
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
hau duc » huu duc, ha duc, pham duc
duc van » duc va, duc tan, duc manh
hanh de » hanh ve, hanh kem
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
de cua » le cua, te cua, dieu cua

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: toc sach v ((nang ma) OR (sang ma)) hoi. ((hieu van) OR (thien van)) hau duc van hanh de cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach v ((nang ma) OR (sang ma)) hoi. ((hieu van) or (thien van)) hau duc van hanh de cua tre~".
• Adding a wildcard symbol may retrieve word variants: toc sach v ((nang ma) OR (sang ma)) hoi. ((hieu van) or (thien van)) hau duc van hanh de cua tre*.