Cannot debug source code in private path

I can debug source code when the file locates in a public path, e.g. Runtime/Renderer/Public/SceneView.h

But, I cannot debug source code when the file locates in a private path, e.g. Runtime/Renderer/Private/SceneRendering.h

Does anybody know why and how to solve the problem?

P.S.
renderer.build.cs has set OptimizeCode as CodeOptimization.Never to enable debug

Solved, pdb can be forcely enabled in target file