Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
nang cho » nang chon, ngang cho, nang cao
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
ty nang » ky nang, ty xang, ty hang
cho hoc » co hoc, khoa hoc
cac vuc » cac nuoc, cac vung, cac cuoc
cua cau » cua cac, cua chu, cua cay
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: ((toc sach) OR (doc sach)) ty nang cho hoc. lieu va cac vuc ((van hanh) or (ban hanh)) vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ty nang cho hoc. lieu va cac vuc ((van hanh) OR (ban hanh)) vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (doc sach)) ty nang cho hoc. lieu va cac vuc ((van hanh) or (ban hanh)) vi cua cau*".