Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh than » hanh han, hanh nhan, hanh phan
hieu van » hieu va, thien van, lieu va
tang ma » mang may, tang van
sach ty » sach y, sach tu, sach thu
van bao » van ban, van dao
bao duc » dao duc, bao luc, cao duc
va hanh » van hanh, va thanh, va danh
nang ma » sang ma, nang cao, mang may
cua tre » cua te, cuu tre, dua tren
su sach » so sach, vu sach

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 ty ((nang ma) OR (tang ma)) hoi. hieu van bao duc va hanh than ((cua tre) OR (cua triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((nang ma) OR (tang ma)) hoi. hieu van bao duc va hanh than ((cua tre) or (cua triet))~".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang ma) OR (tang ma)) hoi. hieu van bao duc va hanh than ((cua tre) or (cua triet))*.