Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
so sach » so sanh, bo sach, hoc sach
dam tuc » dam thuc, dao tuc, nam thuc
hieu ve » hieu va, hieu van
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
co sach » bo sach, cuon sach, hoc sach
ma hoi » mai hoi, xa hoi, ma hoa
dam tu » nam tu, cam tu, tam tu
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (co sach)) ky tang ma hoi. hieu ve ((dam tuc) or (dam tu)) van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) ky tang ma hoi. hieu ve ((dam tuc) OR (dam tu)) van hanh vi cua vat.
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (co sach)) ky tang ma hoi. hieu ve ((dam tuc) or (dam tu)) van hanh vi cua vat*.