items in External HD don’t show up in search

I have two External HD’s one is a seagate USB.. It’s about 6 years old it has to be plugged into the wall for power. My newer HD is a LACIE rugged that I bought from apple, connected through firewire. When I do a search in finder, items in the seagate will show up, but items in the LACIE will not. I thought this was strange and just wondering if there was a way to get finder to get results from the LACIE too?