Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
ban thanh » ban hanh, ban hang
cau treo » cau theo, cau tren, cau triet
hieu van » thien van, lieu va, hieu ve
cay qua » cau qua, cac qua, cay lua
cua tre » cua te, cuu tre, cua triet
qua ban » cua ban, qua quan
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ty nang ma hoi. ((hieu van) OR (hieu va)) cay qua ban thanh van ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ty nang ma hoi. ((hieu van) OR (hieu va)) cay qua ban thanh van ((cua tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ty nang ma hoi. ((hieu van) OR (hieu va)) cay qua ban thanh van ((cua tre) or (cau treo))".
• Adding a wildcard symbol may retrieve word variants: so sach ty nang ma hoi. ((hieu van) OR (hieu va)) cay qua ban thanh van ((cua tre) or (cau treo))*.