Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
ly nang » ky nang, ly hang, ly quang
ly vang » ly hang, ly van, ly quang
hieu va » lieu va, hieu qua
hau duc » huu duc, ha duc, pham duc
duc van » duc va, duc tan, duc manh
hanh de » hanh ve, hanh kem
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang
va hau » van hau, va chau, vat hau
de cua » le cua, te cua, dieu cua

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