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