Changing next and previous post link text

I am new to wordpress and I am building my first site using the Gridalicious Pro theme. I have configured almost everything but I have one problem that I haven't solved yet. How do I change the next and previous post link text. Since my site is in swedish I of course would like swedish text instead. I can't find this option anywhere: Am I blind or how do I do this? It was easy changing the Search... and Read More.... Shouldn't Next and Previous be as easy to change?