使用ADMob Native SwiftUI插件时，需要从Bundle中加载nib文件。以下是加载nib文件的示例代码：

import SwiftUI
import GoogleMobileAds
import UIKit

struct AdView: UIViewRepresentable {

  let adType: GADAdLoaderAdType
  let adUnitID: String

  func makeUIView(context: UIViewRepresentableContext) -> GADUnifiedNativeAdView {
    return GADUnifiedNativeAdView()
  }

  func updateUIView(_ uiView: GADUnifiedNativeAdView, context: UIViewRepresentableContext) {
    let adLoader = GADAdLoader(adUnitID: adUnitID, rootViewController: UIApplication.shared.windows.first?.rootViewController, adTypes: [adType], options: nil)
    adLoader.delegate = uiView
    adLoader.load(GADRequest())
  }

  static func createAdView(nibNamed nibName: String) -> GADUnifiedNativeAdView? {
    guard let nibObjects = Bundle.main.loadNibNamed(nibName, owner: nil, options: nil),
          let adView = nibObjects.first as? GADUnifiedNativeAdView else {
      return nil
    }
    return adView
  }
}

在该示例代码中，createAdView方法在获取Bundle中的nib文件时进行了调用。在加载nib文件时，我们需要传入nib的名称。这样，我们就可以使用ADMob Native SwiftUI插件并从Bundle中加载nib文件，以便在应用程序中显示广告。