Perhaps you should try some spelling variations:
ban hang » ngan hang
van hanh » van thanh, ban hanh, van anh
vinh cuu » dinh cuu, sinh cua, dinh cu
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cau luc » cau truc, cau phuc
va hanh » va thanh, va danh, ban hanh
cuu tre » cua tre, cau tren, cau treo
ve cau » ke cau, va cau, ve cac
x hoi » xa hoi, o hoi, x ho

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 ky nang x hoi. hieu ve cau luc ((((va hanh) or (ban hang))) or (van hanh)) vinh cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang x hoi. hieu ve cau luc ((((va hanh) OR (ban hang))) OR (van hanh)) vinh cuu tre.
• Adding a wildcard symbol may retrieve word variants: so sach ky nang x hoi. hieu ve cau luc ((((va hanh) or (ban hang))) or (van hanh)) vinh cuu tre*.