Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
va hanh » van hanh, va thanh, va danh
van bao » van ban, van dao
van bac » van ban, van hac, dan bac
su sach » so sach, vu sach
mang xa » lang xa, mang may, dang xay
xang xa » lang xa, ang xa, dang xay
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc 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 thu ((xang xa) or (mang xa)) hoi. hieu ((van bac) OR (van bao)) xuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu ((xang xa) OR (mang xa)) hoi. hieu ((van bac) OR (van bao)) xuc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thu ((xang xa) or (mang xa)) hoi. hieu ((van bac) OR (van bao)) xuc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach thu ((xang xa) or (mang xa)) hoi. hieu ((van bac) OR (van bao)) xuc va hanh vi cua tre*.