Perhaps you should try some spelling variations:
xang dai » xang dau, lang dai, hoang dai
bo sach » hoc sach
co sach » cuon sach, hoc sach
dai hoi » dai hoc, dai hai, dai moi
hieu ve » hieu va, hieu van
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va thanh, va danh
ve cam » ve cham, ve cac, va cam
tuc va » thuc va, truc va, tuc xa
vi hoc » li hoc, va hoc
hien » bien, vien, tien

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((bo sach) OR (co sach)) ty xang dai hoi. hieu ve cam tuc va hanh vi hoc hien~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((bo sach) OR (co sach)) ty xang dai hoi. hieu ve cam tuc va hanh vi hoc hien".
• Adding a wildcard symbol may retrieve word variants: ((bo sach) OR (co sach)) ty xang dai hoi. hieu ve cam tuc va hanh vi hoc hien*.