Mouse problem

So we are not filthy people but my husband and I work full time and we have three kids.  Our house is never perfectly clean.  We have started to get mice in our kitchen. I hate finding mice dropping every where.  GRRRRR!  This is the second time this year that we have had this problem.  We bought the snap mouse traps (the others were expensive) and we caught several mice.  The mice droppings stopped so we thought we got them all. We probably did get them all but then they came back again.  I read on a site (don't remember which one) that a good way to kill mice, beyond the snap trap, is to put out a small bowl of cola.  They drink the cola and then can not burp and die.  I did this. Checked on the cola the next morning and it was clearly drank, but now I am thinking this mice or mouse went off and died and it is going to cause quite a stink.  Well if it did it had others because I found more droppings on our counter. UGH!  Guess it is off to the store to buy some snap traps.