Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cao hoc » co hoc, cho hoc, chat hoc
hieu ve » hieu va, hieu van
luc van » luoc van, luu van, luc va
duc van » duc va, duc tan, duc manh
ve cau » ke cau, va cau, ve 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: toc sach ty nang cao hoc. hieu ve cau ((luc van) or (duc van)) hanh vi cua cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty nang cao hoc. hieu ve cau ((luc van) OR (duc van)) hanh vi cua cac*.