Perhaps you should try some spelling variations:
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
cuu tre » cua tre, cau tren, cau treo
vu sac » vu sach, vu san, va sac
sac ky » cac ky, sai ky
di cuu » di cau, di cua, dinh cuu
ve am » va am

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sac ky nang ((x ho) or (xa hoi)). hieu ve am thuc ((va hanh) OR (va danh)) di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sac ky nang ((x ho) OR (xa hoi)). hieu ve am thuc ((va hanh) OR (va danh)) di cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sac ky nang ((x ho) or (xa hoi)). hieu ve am thuc ((va hanh) OR (va danh)) di cuu tre".
• Adding a wildcard symbol may retrieve word variants: vu sac ky nang ((x ho) or (xa hoi)). hieu ve am thuc ((va hanh) OR (va danh)) di cuu tre*.