Perhaps you should try some spelling variations:
nang cau » nang cao, hang cau, nang dau
sach ky » sach ty, sach kem, sach hay
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, tuc xa
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) or (sac ky))) or (sach y)) nang cau hoi. hieu va cam tuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((((sach ky) OR (sac ky))) OR (sach y)) nang cau hoi. hieu va cam tuc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((((sach ky) or (sac ky))) or (sach y)) nang cau hoi. hieu va cam tuc va hanh vi cua tre*.