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