Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
so sang » so sanh, so dang, so lang
sang ky » sang kyo, dang ky, tang ky
cao hoi » cau hoi, co hoi, cao hoc
xuc cac » xuc tac, tuc cac, xuc cam
ve cac » va cac
va cua » va chua, via cua, ma cua
ca cua » co cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sang ky nang cao hoi. hieu ((ve cac) OR (vien cac)) xuc cac dan ((va cua) or (ca cua)) tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sang ky nang cao hoi. hieu ((ve cac) OR (vien cac)) xuc cac dan ((va cua) OR (ca cua)) tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sang ky nang cao hoi. hieu ((ve cac) OR (vien cac)) xuc cac dan ((va cua) or (ca cua)) tu".
• Adding a wildcard symbol may retrieve word variants: so sang ky nang cao hoi. hieu ((ve cac) OR (vien cac)) xuc cac dan ((va cua) or (ca cua)) tu*.