Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
chau tho » chat thom, cau thi, phu tho
chau phu » chau phi, chau au, cho phu
hanh vu » hanh vi, hanh va, hanh tu
su sach » so sach, vu sach
hieu ke » hieu kem, chieu ke, hieu ky
va nang » van nang, da nang, cam nang
xa nang » da nang, xa nong, ca nang
vu va » vu van, tu va, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((xa nang) OR (va nang)) xa hoi. hieu ke ((chau phu) or (chau tho)) van hanh vu va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((xa nang) OR (va nang)) xa hoi. hieu ke ((chau phu) OR (chau tho)) van hanh vu va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((xa nang) OR (va nang)) xa hoi. hieu ke ((chau phu) or (chau tho)) van hanh vu va triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((xa nang) OR (va nang)) xa hoi. hieu ke ((chau phu) or (chau tho)) van hanh vu va triet*.