Use the drop down feature on the upper right where it says "recent activity".  Then click on "newest".

Are you talking about the sort by Drop down? changing from recent activity to newest doesn’t change whether new profiles are being included in the search. Even when  I reset the search, it is still not showing me new profiles. I suppose it’s possible that there have not been any new profiles in the last two weeks within 10 miles of DC, but that would surprise me. Also I have checked the box that says “unviewed” so that I am not seeing profiles that I’ve already seen. Does anybody have any thoughts on this?

Hard to know exacty but maybe try clearing all the filters and starting over. Sometimes you get box checked that doesn't go away.

Here's another  search idea which works, especially if, like me and LesterP and others, you are interested in finding the newest profiles in your searches. The top left corner of every SA screen shows the word seeking in big red letters.  It's a clickable link that takes you to a page of thumbnails grouped into categories: Featured members, New members, Members online now, Popular members, and Most recent search. I have often found new profiles there which for some reason are active on that page but have not made it onto the searchable database yet. So if you're quick to pounce, as I am, you should check it out as a routine part of your searching. You may well find some cuties there before the other guys see them! Disclaimer: I usually access SA on a windows PC. If you use a different device or app I don't know if it works the same.