Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach kem
xa hanh » xa thanh, xa khanh, va hanh
thuc xa » thuc xay, tuc xa, thuc va
sang ma » tang ma, sang tao, mang may
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, nang cao, mang may
sach ty » sach y, sach tu, sach thu
van am » van nam, van lam, van dam
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: tu ((sach ky) or (sach ty)) ((nang ma) OR (sang ma)) hoa. hieu van am thuc xa hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) ((nang ma) OR (sang ma)) hoa. hieu van am thuc xa hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach ty)) ((nang ma) OR (sang ma)) hoa. hieu van am thuc xa hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach ty)) ((nang ma) OR (sang ma)) hoa. hieu van am thuc xa hanh vi cua tre*.