Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
hanh di » hanh vi, hanh de, hang di
xuc van » duc van, luc van, xuc ban
van cam » van lam, van cau, van dam
sach ty » sach y, sach tu, xach tay
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de 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 ty) or (sach thu)) nang xa hoi. hieu ((van cam) OR (van nam)) xuc van hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) nang xa hoi. hieu ((van cam) OR (van nam)) xuc van hanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach thu)) nang xa hoi. hieu ((van cam) OR (van nam)) xuc van hanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) nang xa hoi. hieu ((van cam) OR (van nam)) xuc van hanh di cua tre*.