Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
cac toc » cac toi, cac nuoc, cac thoi
cua tre » cua te, cua triet, dua tren
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
cuu tre » cau tren, cau treo
cac tuc » cac tu, cac tac, cac nuoc
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
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: su sach y nang ma hoi. hieu van ((cac tuc) or (cac toc)) va danh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ma hoi. hieu van ((cac tuc) OR (cac toc)) va danh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: su sach y nang ma hoi. hieu van ((cac tuc) or (cac toc)) va danh vi ((cua tre) or (cuu tre))*.