Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh vai » hanh vi, hanh va, hanh tai
ban hanh » ban hang
hieu van » hieu va, thien van, lieu va
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, dua tren
duc ban » duc tan, duc van, dua ban
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hang ca » hang va, hang tai, hang dau
van cam » van nam, van lam, van cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty ((hang ca) OR (nang cao)) hoi. hieu van cam duc ban hanh vai ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((hang ca) OR (nang cao)) hoi. hieu van cam duc ban hanh vai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((hang ca) OR (nang cao)) hoi. hieu van cam duc ban hanh vai ((cua tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((hang ca) OR (nang cao)) hoi. hieu van cam duc ban hanh vai ((cua tre) or (cua triet))*.