Perhaps you should try some spelling variations:
tao khoi » thao khoa, lao khoa, tao boi
van hanh » van thanh, ban hanh, van anh
cau tren » cu tren, dau tren, ca tren
ky sang » ky nang, ky dang, ky tang
tao hoi » tao boi, tay hoi, thao hoc
va pham » van pham, va phat, va phap
va hanh » va thanh, va danh, ban hanh
vai cau » va cau, van cau, vai cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky sang ((tao hoi) OR (tao khoi)). lieu va pham duc ((va hanh) or (van hanh)) vai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky sang ((tao hoi) OR (tao khoi)). lieu va pham duc ((va hanh) OR (van hanh)) vai cau tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky sang ((tao hoi) OR (tao khoi)). lieu va pham duc ((va hanh) or (van hanh)) vai cau tren*".