Perhaps you should try some spelling variations:
te sach » toc sach
sach ky » sac ky, sach y, sach ty
duc ban » duc tan, duc van, dua ban
luc ban » cuc ban, luc bat, luc van
hieu va » lieu va, hieu qua
hieu ve » hieu van
nang o » nang co, nang ho, nang ro
vi cua » vai cua, di cua
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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 ky nang o hoi. ((hieu ve) OR (hieu va)) cam ((luc ban) or (duc ban)) hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang o hoi. ((hieu ve) OR (hieu va)) cam ((luc ban) OR (duc ban)) hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang o hoi. ((hieu ve) OR (hieu va)) cam ((luc ban) or (duc ban)) hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang o hoi. ((hieu ve) OR (hieu va)) cam ((luc ban) or (duc ban)) hanh vi cua te*.