Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
va hanh » van hanh, va thanh, va danh
cam thu » nam thu, cac thu, ca thu
qua cam » qua cham, qua cac, qua ca
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
thu va » thuc va, thue va, tu va
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)) ((nang xa) OR (nang ma)) hoi. hieu qua cam thu va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) ((nang xa) OR (nang ma)) hoi. hieu qua cam thu va hanh vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) or (sac ky)) ((nang xa) OR (nang ma)) hoi. hieu qua cam thu va hanh vi cua tre*".