Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
banh vi » hanh vi, ban vi, benh vi
duc ban » duc tan, duc van, dua ban
xuc ban » cuc ban, quoc ban, xuat ban
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
ty lang » tay lang, ty xang, ty hang
vu sach » vu bach, su sach, vu khach
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 (vu sach)) ty lang xa hoi. hieu van nam ((xuc ban) OR (duc ban)) banh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu sach)) ty lang xa hoi. hieu van nam ((xuc ban) OR (duc ban)) banh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (vu sach)) ty lang xa hoi. hieu van nam ((xuc ban) OR (duc ban)) banh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) ty lang xa hoi. hieu van nam ((xuc ban) OR (duc ban)) banh vi cua tre*.