Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, me hoi
cam lo » nam lo, cam ly, cam o
nam so » nam sao, nam bo
vi cua » vai cua, di cua

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 ky nang ((ma hoi) or (ma hoa)). hieu van ((cam lo) or (nam so)) va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((ma hoi) OR (ma hoa)). hieu van ((cam lo) OR (nam so)) va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((ma hoi) or (ma hoa)). hieu van ((cam lo) or (nam so)) va hanh vi cua tre*.