Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
kho tang » cao tang
thanh di » thanh doi, thanh de, thanh do
su sach » so sach, vu sach
ky lang » ky nang, ky dang, ky tang
cua tre » cuu tre, cua triet, dua tren
hieu ve » hieu va, hieu van
cac luc » cau luc, coc luc, cac nuoc
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va
cua te » cua tu

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 lang) OR (kho tang)) xa hoi. hieu ve cac luc va thanh di ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky lang) or (kho tang)) xa hoi. hieu ve cac luc va thanh di ((cua tre) OR (cua te))~".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky lang) or (kho tang)) xa hoi. hieu ve cac luc va thanh di ((cua tre) OR (cua te))*.