Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach tu, sach thu
xang co » nang co, lang co, tang co
hieu ve » hieu va
cau luc » cau truc, cau phuc
luc van » luoc van, luu van, duc van
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 ty xang co hoc. ((hieu ve) or (hieu van)) cau luc van hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty xang co hoc. ((hieu ve) OR (hieu van)) cau luc van hanh vi cua cau*.