Perhaps you should try some spelling variations:
nang tai » hang tai, tang tai, sang tai
toan ban » van ban
toan cau » toan cao, toan tap, toan tai
ban hanh » ban hang
cuc ban » cua ban, cac ban, cuu ban
te sach » toc sach
cac cuc » cac cuoc, cac cua, cac nuoc
hieu ve » hieu van
tai hoi » tai khoi, dai hoi, tai hai
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang

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 y nang tai hoi. ((hieu ve) or (hieu va)) cac cuc ban hanh ((toan cau) OR (toan ban)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang tai hoi. ((hieu ve) OR (hieu va)) cac cuc ban hanh ((toan cau) OR (toan ban)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang tai hoi. ((hieu ve) or (hieu va)) cac cuc ban hanh ((toan cau) OR (toan ban)) tren".
• Adding a wildcard symbol may retrieve word variants: te sach y nang tai hoi. ((hieu ve) or (hieu va)) cac cuc ban hanh ((toan cau) OR (toan ban)) tren*.