Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
hanh di » hanh vi, hanh de, hang di
duc van » duc va, duc tan, duc manh
cuu tre » cua tre, cau tren, cau treo
sach ty » sach y, sach tu, sach thu
ty tang » tay tang, ty xang, ty hang
ha duc » ho duc, ha dac, xa duc
ma hoi » mai hoi, ma hoa, me hoi
van ha » van hoa, van chat, van phan

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 ty tang ((ma hoi) OR (xa hoi)). hieu van ha duc van hanh di ((cua triet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty tang ((ma hoi) OR (xa hoi)). hieu van ha duc van hanh di ((cua triet) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty tang ((ma hoi) OR (xa hoi)). hieu van ha duc van hanh di ((cua triet) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: thu sach ty tang ((ma hoi) OR (xa hoi)). hieu van ha duc van hanh di ((cua triet) or (cuu tre))*.