Steps to reproduce:
1. Open the attached “Test.zip” project
2. In the Project Window, select the “Sphere.prefab”
3. In the Inspector Window, set the Label to “Label”
4. In the Project Window Search Bar, type “l:Label:
5. Observe that the “Sphere.prefab” is shown in the Search results
6. Click Window → Search → New Window
7. In the Search Bar type “l:Label”
8. Observe the results

Expected result: The “Sphere.prefab” is shown in the Search results
Actual result: The Search results are empty

Reproducible in: 6000.0.30f1, 6000.0.40f1
Not reproducible in: 2022.3.59f1, 6000.0.29f1, 6000.1.0b8, 6000.2.0a5

Reproducible on: Windows 11
Not reproducible on: No other environment tested

Note: Not reproducible on an empty project