Perhaps you should try some spelling variations:
van thanh » ban thanh
thai cua » than cua, tai cuc, tri cua
van tuan » van quan, van ban, anh tuan
lang van » dang van, tang van, hoang van
te sach » toc sach
cam duc » cam xuc, cao duc, pham duc
hieu va » lieu va, hieu qua
sach tu » sach thu, cach tu, sach ty
tang ma » mang may, tang van
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao

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 ((tang ma) or (lang van)) hoi. hieu va cam duc ((van thanh) OR (van tuan)) thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu ((tang ma) OR (lang van)) hoi. hieu va cam duc ((van thanh) OR (van tuan)) thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tu ((tang ma) or (lang van)) hoi. hieu va cam duc ((van thanh) OR (van tuan)) thai cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach tu ((tang ma) or (lang van)) hoi. hieu va cam duc ((van thanh) OR (van tuan)) thai cua tre*.