The following attributes can be specified in a search when the art kind is set to Blend:
The kind of spacing the blend uses: either Smooth Color, Specified Steps, or Specified Distance. When set to Specified Steps, the number of steps can be specified, with is less than, is equal to, and is more than.
FindReplace Art Blend Spacing Controls
Whether or not the blend has a custom-defined spline.
FindReplace Art Blend Spline Controls