Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thai cuu » thai cua, tai cuc, thi cuc
dau nuoc » dat nuoc, dau ngoc, cap nuoc
te sach » toc sach
van dau » van dao, phan dau
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
cuu tre » cua tre, cau tren, cau treo
va dan » ca dan, va dau, va dap
va dao » ca dao

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 ((ky lang) OR (ky tang)) xa hoi. hieu van dau nuoc ((va dan) or (va dao)) thai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ky lang) OR (ky tang)) xa hoi. hieu van dau nuoc ((va dan) OR (va dao)) thai cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ky lang) OR (ky tang)) xa hoi. hieu van dau nuoc ((va dan) or (va dao)) thai cuu tre*".