You can have one displacement map and one bump map. But I'd say it would be better to make the displacement map better. Remember white is FULL displacement, black is NO displacement. Grey is somewhere in-between. Make the lines on the costume a darker grey so they won't displace as much as the eyes :)

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.