Perhaps you should try some spelling variations:
mai khoi » mai khoa, cac khoi, dai khoa
tai khoa » da khoa, noi khoa
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
xuc va » tuc va, luc va, xac va
va cua » va chua, via cua, ca cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((mai khoi) OR (tai khoa)). hieu ve cham ((xuc va) OR (duc va)) hanh va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((mai khoi) OR (tai khoa)). hieu ve cham ((xuc va) or (duc va)) hanh va cua tre~".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((mai khoi) OR (tai khoa)). hieu ve cham ((xuc va) or (duc va)) hanh va cua tre*.