Having finished in the top half of the table for the last two seasons, the hosts went into this match with just one victory from their first nine fixtures this term.
However, they doubled that tally with a convincing success against opponents who have now suffered four straight defeats.
Den Haag goalkeeper Martin Hansen was forced to save from Robin Gosens early on, while Filip Kurto kept out a decent Gianni Zuiverloon free-kick at the other end.
Kramer then continued his hot streak by netting on 17 minutes following good work from Xander Houtkoop.
At that point, the striker had scored eight of his side's last 10 goals.
Kramer almost added another at the beginning of the second period after being set up by Mathias Gehrt, while Vito Wormgoor also tested Kurto.
Gehrt did double the advantage on 74 minutes when coolly putting the ball over the goalkeeper.
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