Perhaps you should try some spelling variations:
cac vung » cac ung, cac chung, cach dung
te sach » toc sach
sach ty » sach y, sach tu, sach thu
van anh » van thanh, tuan anh, van minh
cac vuc » cac nuoc, cac cuoc, cac quoc
hieu ve » hieu va, hieu van
cho hoc » khoa hoc
ty nang » ky nang, ty xang, ty hang
cua cau » cua cac, cua chu, cua cay
anh vi » hanh vi, anh va, anh ve
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: te sach ty nang ((cho hoc) or (co hoc)). hieu ve ((cac vuc) OR (cac vung)) van anh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((cho hoc) OR (co hoc)). hieu ve ((cac vuc) OR (cac vung)) van anh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ((cho hoc) or (co hoc)). hieu ve ((cac vuc) OR (cac vung)) van anh vi cua cau*".