Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh vai » hanh va, hanh tai, hanh van
su sach » so sach, vu sach
tuc ban » thuc ban, truc ban, tu ban
hac tuc » thac toc, thai tuc
sach ky » sac ky, sach y, sach ty
van hac » van hoc, van ha, van hai
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
cua tre » cua te, cuu tre, cua triet

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 ky ((nang ma) OR (sang ma)) hoi. hieu van hac tuc ban ((hanh vai) or (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang ma) OR (sang ma)) hoi. hieu van hac tuc ban ((hanh vai) OR (hanh vi)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang ma) OR (sang ma)) hoi. hieu van hac tuc ban ((hanh vai) or (hanh vi)) cua tre*".