Linoleum repair

We have several "slits" in our floor. Kinda looks like there was/were some 'air bubbles' and installers just decided to give a slit to let bubble disappear. Did not notice till a couple of months into ownership and light shined just right. We did use the throw rug thing, but have decided to refloor. Three of our slits are longer than 3 inces and are buckling worse as time goes on.