Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh vai » hanh vi, hanh va, hanh tai
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
thi hang » thi hanh, thi nang, thi hong
nam duc » nam duoc, pham duc, nam thuc
duc van » duc va, duc tan, duc manh
ty hang » ly hang, ty xang, thu hang
cua tre » cua te, cuu tre, dua tren
su sach » so sach, vu sach
ca hoi » cau hoi, cua hoi, xa hoi

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) or (thi hang)) ca hoi. hieu van nam duc van hanh vai ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty hang) OR (thi hang)) ca hoi. hieu van nam duc van hanh vai ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: su sach ((ty hang) or (thi hang)) ca hoi. hieu van nam duc van hanh vai ((cua tre) or (cua triet))*.