Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
cau treo » cau theo, cau tren, cau triet
te sach » toc sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
vai cau » va cau, van cau, vai cac
ma hoi » ma hoa, me hoi, va hoi
cac co » cac cong
co van » cao van, vo van, so van

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 ky nang ((((ma hoi) OR (mai hoi))) or (xa hoi)). hieu va cac co van hanh vai cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((((ma hoi) OR (mai hoi))) OR (xa hoi)). hieu va cac co van hanh vai cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((((ma hoi) OR (mai hoi))) or (xa hoi)). hieu va cac co van hanh vai cau treo".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((((ma hoi) OR (mai hoi))) or (xa hoi)). hieu va cac co van hanh vai cau treo*.