Perhaps you should try some spelling variations:
vu thanh » su thanh, vu khanh, cuu thanh
hai truc » dai truc, hai trac, hang truc
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
thanh ky » hanh ky, than ky, thanh tay
vai cua » dai cua, hai cua, lai cua
va hanh » va thanh, va danh, ban hanh
van hai » van ha, van chat, van phan
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu thanh ky ((nang xa) OR (nang ma)) hoi. hieu van hai truc ((va hanh) or (van hanh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu thanh ky ((nang xa) OR (nang ma)) hoi. hieu van hai truc ((va hanh) OR (van hanh)) vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu thanh ky ((nang xa) OR (nang ma)) hoi. hieu van hai truc ((va hanh) or (van hanh)) vai cua tre*".