You can search for features in vector layers. The search is currently performing the same as the all layers locator filter in QGIS (accessible in QGIS locator bar using af prefix).

Configure search in QGIS

1. Choose the layers which are searchable in Project --> Project Properties --> Identify Layers{.interpreted-text role="menuselection"}
2. Define the display expression for the concerned layers, this will be used for searching for features. This is configured under Vector Layer Properties --> Display{.interpreted-text role="menuselection"} page