Perhaps you should try some spelling variations:
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
te sach » toc sach
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
va nang » van nang, da nang, cam nang
ma hoi » mai hoi, xa hoi, ma hoa
ve cac » va cac, vien cac
v nang » vu nang, van nang, voi nang
di cua » dai cua, doi cua, de 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 ((v nang) or (va nang)) ma hoi. hieu ve cac luc ((van hanh) OR (ban hanh)) di cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((v nang) OR (va nang)) ma hoi. hieu ve cac luc ((van hanh) OR (ban hanh)) di cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((v nang) or (va nang)) ma hoi. hieu ve cac luc ((van hanh) OR (ban hanh)) di cua tu".
• Adding a wildcard symbol may retrieve word variants: te sach ((v nang) or (va nang)) ma hoi. hieu ve cac luc ((van hanh) OR (ban hanh)) di cua tu*.