Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
xang xa » lang xa, ang xa, dang xay
mang xa » lang xa, mang may, dang xay
hieu vu » hieu ve, hieu su, dieu vu
hieu va » lieu va, hieu qua
soc van » hoc van, oc van, sac van
cua tre » cua te, cuu tre, cua triet
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 ty ((xang xa) OR (mang xa)) hoi. ((hieu vu) or (hieu va)) cham soc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((xang xa) OR (mang xa)) hoi. ((hieu vu) OR (hieu va)) cham soc van hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((xang xa) OR (mang xa)) hoi. ((hieu vu) or (hieu va)) cham soc van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((xang xa) OR (mang xa)) hoi. ((hieu vu) or (hieu va)) cham soc van hanh vi cua tre*.