Perhaps you should try some spelling variations:
quoc ban » quoc bao, quoc lan, quoc quan
ban hanh » ban hang
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
tu san » thu san, tu ban, tu can
san ky » sang ky, van ky, dan ky
va cam » va cham, va cac, va cao
ve cai » va cai, ve tai, ve cau
ve cac » va cac, vien cac
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu san ky nang xa hoi. hieu ((((va cam) or (ve cai))) or (ve cac)) quoc ban hanh vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky nang xa hoi. hieu ((((va cam) OR (ve cai))) OR (ve cac)) quoc ban hanh vi cau tren.
• Adding a wildcard symbol may retrieve word variants: tu san ky nang xa hoi. hieu ((((va cam) or (ve cai))) or (ve cac)) quoc ban hanh vi cau tren*.