Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
nam xua » nam cua, nam mua, nam qua
nam xuc » cam xuc, nam thuc, nam duoc
tu sach » thu sach, te sach, tu cach
nang xa » nang x, lang xa, nang ma
tu nang » tru nang, tu nong, tu nano
su sach » so sach, vu sach
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) OR (su sach)) tu nang xa hoi. hieu van ((nam xuc) or (nam xua)) ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) tu nang xa hoi. hieu van ((nam xuc) OR (nam xua)) ban hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) tu nang xa hoi. hieu van ((nam xuc) or (nam xua)) ban hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) tu nang xa hoi. hieu van ((nam xuc) or (nam xua)) ban hanh vi cua tre*.