Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
toc sach » hoc sach, doc sach, nuoc sach
cac vung » cac ung, cac chung, cach dung
nang cho » nang chon, ngang cho, nang cao
van anh » van thanh, tuan anh, van minh
cac vuc » cac nuoc, cac cuoc, cac quoc
cua cau » cua cac, cua chu, cua cay
hieu ve » hieu va, hieu van
cho hoc » co hoc, khoa hoc
ty nang » ky nang, ty xang, ty hang
anh va » hanh va
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) OR (thuoc sach)) ty nang cho hoc. hieu ve ((cac vuc) or (cac vung)) van anh va cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) ty nang cho hoc. hieu ve ((cac vuc) OR (cac vung)) van anh va cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) ty nang cho hoc. hieu ve ((cac vuc) or (cac vung)) van anh va cua cau*".