Perhaps you should try some spelling variations:
sach van » sach va, bach van, cach van
sach han » sach tham, sach danh, sach nang
van hanh » van thanh, ban hanh, van anh
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
dau xuc » dau xac, dau nuoc
dau xua » dau cua, dao xuan, dau luan
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: tu ((sach van) OR (sach han)) nang xa hoi. hieu va ((dau xuc) or (dau xua)) van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach van) OR (sach han)) nang xa hoi. hieu va ((dau xuc) OR (dau xua)) van hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach van) OR (sach han)) nang xa hoi. hieu va ((dau xuc) or (dau xua)) van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach van) OR (sach han)) nang xa hoi. hieu va ((dau xuc) or (dau xua)) van hanh vi cua tre*.