Perhaps you should try some spelling variations:
ban hanh » ban hang
so sanh » do sanh
ty nang » ky nang, ty xang, ly nang
hanh ca » hanh cac, hanh cat, hanh cua
ty hang » ly hang, ty xang, thi hang
duc ban » duc tan, duc van, dua ban
va cao » va cac, va co, va dao
ca cua » co cua
ve cac » va cac, vien cac
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: so sanh ((ty nang) OR (ty hang)) o hoi. hieu ((ve cac) or (va cao)) duc ban hanh ca cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh ((ty nang) OR (ty hang)) o hoi. hieu ((ve cac) OR (va cao)) duc ban hanh ca cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh ((ty nang) OR (ty hang)) o hoi. hieu ((ve cac) or (va cao)) duc ban hanh ca cua te".
• Adding a wildcard symbol may retrieve word variants: so sanh ((ty nang) OR (ty hang)) o hoi. hieu ((ve cac) or (va cao)) duc ban hanh ca cua te*.