Perhaps you should try some spelling variations:
sach ty » sach tu, sach thu, xach tay
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
lo van » le van, vo van, so van
lao va » tao va, cao va, bao 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: te ((sach y) or (sach ty)) nang ma hoa. hieu va cam ((lo van) or (lao va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach y) OR (sach ty)) nang ma hoa. hieu va cam ((lo van) OR (lao va)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: te ((sach y) or (sach ty)) nang ma hoa. hieu va cam ((lo van) or (lao va)) hanh vi cua tre*.