Perhaps you should try some spelling variations:
danh sai » dung sai, danh bat, danh dau
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, tu cach
sai cua » dai cua, hai cua, lai cua
xa danh » va danh, dia danh, nam danh
cau tuc » cau truc, cau tu, cau luc
van cau » van dau, van hau, van chat
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
te sach » toc sach
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) OR (te sach)) ((ky lang) or (ky dang)) xa hoi. hieu van cau tuc xa danh sai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ((ky lang) OR (ky dang)) xa hoi. hieu van cau tuc xa danh sai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (te sach)) ((ky lang) or (ky dang)) xa hoi. hieu van cau tuc xa danh sai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (te sach)) ((ky lang) or (ky dang)) xa hoi. hieu van cau tuc xa danh sai cua tre*.