Perhaps you should try some spelling variations:
thien van » thi van
cau treo » cau theo, cau tren, cau triet
manh hai » lanh hai, minh hai, thanh hai
hieu van » hieu va, lieu va, hieu ve
thuc va » thuc vat, thuc dan, thuc day
hai cau » hai chau, hai chu, hai hau
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
tuc va » truc va, tuc xa, duc va
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 ky nang ma hoi. ((hieu van) or (thien van)) lam ((tuc va) or (thuc va)) manh hai cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang ma hoi. ((hieu van) OR (thien van)) lam ((tuc va) OR (thuc va)) manh hai cau treo.
• Adding a wildcard symbol may retrieve word variants: so sach ky nang ma hoi. ((hieu van) or (thien van)) lam ((tuc va) or (thuc va)) manh hai cau treo*.