Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach tu, sach thu
va hanh » va thanh, va danh, ban hanh
cau tuc » cau truc, cau tu, cau luc
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
ty nang » ky nang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, ma hoa
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 ty nang ma hoi. ((hieu ve) or (hieu qua)) cau tuc ((va hanh) or (van hanh)) vu va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang ma hoi. ((hieu ve) OR (hieu qua)) cau tuc ((va hanh) OR (van hanh)) vu va triet.
• Adding a wildcard symbol may retrieve word variants: su sach ty nang ma hoi. ((hieu ve) or (hieu qua)) cau tuc ((va hanh) or (van hanh)) vu va triet*.