How to make more folders available offline on my new computer?

Hi there,

I've had to set up a new laptop after a power failure in my old one. So I relied on my Dropbox account to set up my folders that sit under the Dropbox folder. It asked me which folders I wanted to set up on my laptop, and I only highlighted a selection, thinking I could bring in others later. Now I can only see the option to download a folder rather than make it synch with Dropbox and my  laptop. The majority of my folders under the dropbox directory are now online only on the dropbox.com. 

On my folder structure on my Mac, I can't see the other folders that I didn't select to bring into  the new laptop. So I'm not seeing smart folders, folders that are online and not downloaded. 
How do I get back to my folders on my actual laptop that synch with dropbox?

Thanks!