Perhaps you should try some spelling variations:
thanh hoa » thanh pho
ban thanh » ban hanh, ban hang
hieu dan » hieu van, sieu dan, hieu quan
hieu dac » hieu cac, bieu dac, chieu day
gian duc » giao duc, gia duc, gian dac
cua tre » cua te, cuu tre, cua triet
duc ban » duc tan, duc van, dua ban
ky tang » ky nang, kho tang, ky trong
hoa cua » hoa chat, hoa xuat
ky dang » ky nang, ky danh
su sac » su sach, su cac, su xac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ((ky tang) or (ky dang)) xa hoi. ((hieu dan) OR (hieu dac)) gian duc ban thanh hoa cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ((ky tang) OR (ky dang)) xa hoi. ((hieu dan) OR (hieu dac)) gian duc ban thanh hoa cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ((ky tang) or (ky dang)) xa hoi. ((hieu dan) OR (hieu dac)) gian duc ban thanh hoa cua tre".
• Adding a wildcard symbol may retrieve word variants: su sac ((ky tang) or (ky dang)) xa hoi. ((hieu dan) OR (hieu dac)) gian duc ban thanh hoa cua tre*.