Perhaps you should try some spelling variations:
van thiet » va thiet, dan thiet, can thiet
chau phu » chau phi, chau au, chau tho
ban hanh » ban hang
su sach » so sach, vu sach
sach lo » sach dao, sach doi, sach hoi
lo nang » ho nang, ly nang, loai nang
cao hoi » cau hoi, co hoi, cao hoc
hieu va » lieu va, hieu qua
va chau » va chat, va cau, va cham
va hanh » van hanh, va thanh, va danh

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 lo nang cao hoi. hieu va chau phu ((va hanh) or (ban hanh)) vi van thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach lo nang cao hoi. hieu va chau phu ((va hanh) OR (ban hanh)) vi van thiet.
• Adding a wildcard symbol may retrieve word variants: su sach lo nang cao hoi. hieu va chau phu ((va hanh) or (ban hanh)) vi van thiet*.