When creating a SmartView for your features, you have the option of selecting "Display related requirements using interactive tree" in Step-6.

When you select this option, the view will display all requirements related to a given feature using an "interactive tree" as shown in this image. This enables you to easily view requirements associated with a feature using a format like:

• Feature
  • Requirement-1
    • Sub-Requirement
      • Sub-Sub-Requirement
        • etc... (unlimited levels)
  • Requirement-2
    • Sub-Requirement
  • Requirement-3
  • ...
  • Requirement-N