Perhaps you should try some spelling variations:
mai khoi » mai khoa, tai khoa, dai khoa
cac khoi » cac thoi, cac khoan, cach thoi
cuu tre » cua tre, cau tren, cau treo
va hanh » van hanh, va thanh, ban hanh
tai cuu » tai cuc, tai buu, tai cua
hieu ve » hieu va, hieu van
va danh » va dinh, va dan, dia danh
cac xuc » cam xuc, cac nuoc, chat xuc
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky nang ((mai khoi) or (cac khoi)). hieu ve cac xuc ((va hanh) OR (va danh)) tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky nang ((mai khoi) OR (cac khoi)). hieu ve cac xuc ((va hanh) OR (va danh)) tai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky nang ((mai khoi) or (cac khoi)). hieu ve cac xuc ((va hanh) OR (va danh)) tai cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sac ky nang ((mai khoi) or (cac khoi)). hieu ve cac xuc ((va hanh) OR (va danh)) tai cuu tre*.