Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cau luoc » cau luc, muu luoc, hau loc
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve cau » ke cau, va cau, ve cac
vi cua » vai cua, di cua
cua tu » cua tuc, cua su, cua cu

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) or (toc sach)) ky nang xa hoi. hieu ve cau luoc ((van hanh) OR (ban hanh)) vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang xa hoi. hieu ve cau luoc ((van hanh) OR (ban hanh)) vi cua tu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) ky nang xa hoi. hieu ve cau luoc ((van hanh) OR (ban hanh)) vi cua tu*".