Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
dau tren » dau tien, dat tren, dau tieng
tu sach » thu sach, su sach, te sach
mang xa » lang xa, mang may, dang xay
xuc van » duc van, luc van, vuc van
y mang » cay mang
va cau » van cau, va dau, va cao
vi dau » vi dai, va dau, bi dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y mang xa hoi. hieu ((va cau) OR (va cac)) xuc van hanh vi dau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y mang xa hoi. hieu ((va cau) OR (va cac)) xuc van hanh vi dau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach y mang xa hoi. hieu ((va cau) OR (va cac)) xuc van hanh vi dau tren*.