Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
thanh tan » thanh tuan, thanh san, thanh van
thu sach » tu sach, thuat sach, thuoc sach
duc ban » duc tan, duc van, dua ban
cao duc » dao duc, cao suc, giao duc
sach ky » sac ky, sach y, sach ty
hieu va » hieu qua
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang ma hoi. ((hieu va) or (lieu va)) cao duc ban ((thanh tan) OR (thanh toan)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ma hoi. ((hieu va) OR (lieu va)) cao duc ban ((thanh tan) OR (thanh toan)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang ma hoi. ((hieu va) or (lieu va)) cao duc ban ((thanh tan) OR (thanh toan)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ma hoi. ((hieu va) or (lieu va)) cao duc ban ((thanh tan) OR (thanh toan)) cua tre*.