Perhaps you should try some spelling variations:
ban thanh » ban hang
van triet » va triet, van thiet, hanh triet
van trieu » tan trieu, van tieu, van hieu
cam thuc » am thuc, nam thuc, cam thu
ban hanh » ban hang
vu sach » vu bach, su sach, vu khach
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
va cam » va cham, va cac, va cao

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach y nang ma hoi. hieu va cam thuc ((ban thanh) OR (ban hanh)) va ((van triet) or (van trieu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y nang ma hoi. hieu va cam thuc ((ban thanh) OR (ban hanh)) va ((van triet) OR (van trieu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y nang ma hoi. hieu va cam thuc ((ban thanh) OR (ban hanh)) va ((van triet) or (van trieu))".
• Adding a wildcard symbol may retrieve word variants: vu sach y nang ma hoi. hieu va cam thuc ((ban thanh) OR (ban hanh)) va ((van triet) or (van trieu))*.