Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
vuc van » duc van, luc van, thuc van
xuc van » duc van, luc van, xuc ban
hieu ve » hieu va, hieu van
cao hoc » co hoc, cho hoc, chat hoc
ty nang » ky nang, ty xang, ty hang
cua cau » cua cac, cua chu, cua cay
ve cac » va cac, vien cac
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: ((te sach) or (toc sach)) ty nang cao hoc. hieu ve cac ((xuc van) OR (vuc van)) hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ty nang cao hoc. hieu ve cac ((xuc van) OR (vuc van)) hanh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) ty nang cao hoc. hieu ve cac ((xuc van) OR (vuc van)) hanh vi cua cau*".