Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
than cua » nhan cua, thai cua, gian cua
hieu ve » hieu va, hieu van
ban cua » ban quan
tu sac » tu sach, tu cac, tu san
tu can » tu ban, tu cac, thu canh
nang o » nang co, nang ho, nang ro
ve cac » va cac, vien cac
du van » duy van, duc van, tu van
o lai » o lao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sac) or (tu can)) ky nang o lai. hieu ve cac du van hanh ((than cua) OR (ban cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (tu can)) ky nang o lai. hieu ve cac du van hanh ((than cua) OR (ban cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sac) or (tu can)) ky nang o lai. hieu ve cac du van hanh ((than cua) OR (ban cua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (tu can)) ky nang o lai. hieu ve cac du van hanh ((than cua) OR (ban cua)) tre*.