Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thi nang » thi cong, ki nang
thi hanh » thi thanh
vuc van » duc van, luc van, thuc van
cac vuc » cac nuoc, cac vung, cac cuoc
hieu ve » hieu va, hieu van
cua cau » cua cac, cua chu, cua cay
cho hoc » co hoc, khoa hoc
ve cac » va cac, vien cac
anh vi » anh va, anh ve, anh vu

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 ((thi nang) OR (thi hanh)) cho hoc. hieu ve cac vuc van ((anh vi) or (hanh vi)) cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((thi nang) OR (thi hanh)) cho hoc. hieu ve cac vuc van ((anh vi) OR (hanh vi)) cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((thi nang) OR (thi hanh)) cho hoc. hieu ve cac vuc van ((anh vi) or (hanh vi)) cua cau*".