Perhaps you should try some spelling variations:
su sach » so sach, vu sach
tinh vi » trinh vi, tinh voi, tinh va
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
xay hoi » tay hoi, cay phoi, gay thoi
ky dang » ky nang, ky danh
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua
ve coc » ve cuoc, ve cac, ve co

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky dang ((xay hoi) OR (xa hoi)). hieu ve coc ((luc va) OR (tuc va)) tinh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky dang ((xay hoi) OR (xa hoi)). hieu ve coc ((luc va) or (tuc va)) tinh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky dang ((xay hoi) OR (xa hoi)). hieu ve coc ((luc va) or (tuc va)) tinh vi cua tre*.