Perhaps you should try some spelling variations:
dang xay » dang van, van xay
cua tre » cua te, cua triet, dua tren
va danh » va dinh, va dan, dia danh
cuu tre » cau tren, cau treo
va hanh » van hanh, va thanh, ban hanh
cac tuc » cac toc, cac tu, cac tac
hieu va » lieu va, hieu qua
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh
sac ky » cac ky, sai ky
tu sac » tu sach, tu cac, tu san

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 ky dang xay hoi. hieu va cac tuc ((va hanh) OR (va danh)) tai ((cuu tre) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky dang xay hoi. hieu va cac tuc ((va hanh) OR (va danh)) tai ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky dang xay hoi. hieu va cac tuc ((va hanh) OR (va danh)) tai ((cuu tre) or (cua tre))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky dang xay hoi. hieu va cac tuc ((va hanh) OR (va danh)) tai ((cuu tre) or (cua tre))*.