Translation:The country needs to produce more ships.
I'm still learning too, but I think that flere is used to mean "more" when you're talking about something countable. So you'd say "several boxes", and "more boxes", and in Norwegian both would be flere esker. I think context determines whether it's "several" or "more".
On the other hand, if you're talking about something uncountable (e.g. water, air, cake), then you would use "some water" and "more water", and that would be noe vann and mer vann.