Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban thanh » ban hanh, ban hang
doc sach » hoc sach, toc sach, nuoc sach
thanh va » thanh van, hanh va, thanh ha
cac duc » cac du, cao duc, cac dac
cua tre » cua te, cuu tre, dua tren
duc ban » duc tan, duc van, dua ban
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
ve cac » va cac, vien cac

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 (doc sach)) ky tang xa hoi. hieu ve cac duc ban thanh va ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (doc sach)) ky tang xa hoi. hieu ve cac duc ban thanh va ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (doc sach)) ky tang xa hoi. hieu ve cac duc ban thanh va ((cua tre) or (cua triet))*.