I assume your news items have the correct created dates (which are actually date time). So when you search, you need to bracket the created date time by the start of current date and the start of next date.

For example, assume news1 was created on 9/10 11AM. You search on news where the created date >= 9/10 12AM and created date < 9/11 12AM.

Use the current date:extract date and current date:extract date:+day:1 (or something like that) to get those 2 dates.