Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
van cac » van hac, van cau, van bac
cac duc » cac du, cao duc, cac dac
cua tre » cuu tre, cua triet, dua tren
hang x » hoang xa, chang xu, hang nxb
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach tu ((hang x) OR (nang x)) hoi. hieu van cac duc va thanh dai ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu ((hang x) OR (nang x)) hoi. hieu van cac duc va thanh dai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tu ((hang x) OR (nang x)) hoi. hieu van cac duc va thanh dai ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: te sach tu ((hang x) OR (nang x)) hoi. hieu van cac duc va thanh dai ((cua tre) or (cua te))*.