The work area (user interface) > Viewports > Drawlist > Clear a viewport's drawing list
  
Clear a viewport's drawing list
By clearing a viewport, you hide all objects in the viewport.
1. Open the Structure Browser.
2. Right-click in the structure browser and click Drawlist > Clear.
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The objects cleared from the viewport are NOT deleted; Creo Elements/Direct Modeling simply does not display them in the specified viewport.