Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
hai quan » tac quan
tap quan » tac quan
thu sach » tu sach, thuat sach, thuoc sach
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
duc van » duc va, duc tan, duc manh
mai hoi » mai khoi, dai hoi, lai hoi
cao duc » dao duc, cao suc, giao duc
ve cao » va cao, ve bao, ve cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang ((mai hoi) or (ma hoa)). hieu ve cao duc van thanh ((tap quan) OR (hai quan)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ((mai hoi) OR (ma hoa)). hieu ve cao duc van thanh ((tap quan) OR (hai quan)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang ((mai hoi) or (ma hoa)). hieu ve cao duc van thanh ((tap quan) OR (hai quan)) viet".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((mai hoi) or (ma hoa)). hieu ve cao duc van thanh ((tap quan) OR (hai quan)) viet*.