Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
van hau » van ha, van hai, van dau
hau duc » huu duc, ha duc, pham duc
duc van » duc va, duc tan, duc manh
hanh de » hanh ve, hanh kem
cuu tre » cua tre, cau tren, cau treo
y nang » ly nang, v nang, may nang

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

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