The picture is a guide to the paper test - stand on your skis [wearing your ski boots on a smooth, uncarpeted surface.  Balance evenly on both skis and a helper to should be able to slide a piece of paper under the central area of you ski - from a point just behind your heels to about 30 cm in front of your toes. This is your kick zone - mark both ends.

If your helper can't move the paper, your skis are too soft for you [or you've got heavier since your bought them] and you need a stiffer pair for more efficient ski-ing. 

You can also check if the skis are too stiff for you.  Shift all your weight on to one ski - your helper should not be able to move the paper, if they can then the skis are too stiff and you won't be able to press it down easily for a good kick.  Check both skis.