The ASW helicopters have surface search radar, dipping sonar, sonobuoys, and magnetic anomaly detectors.
From the en.wikipedia.org
The MH-60R carries an acoustic sonar suite to give greater range for locating submarines, and a multi-mode, long-range search radar to locate and monitor surface vessels.
From the washingtontimes.com
Authorities used a dog trained to detect the scent of human remains as well as ground-penetrating radar that can search up to 25 feet below the surface.
From the sacbee.com
They search for the electronic signals emitted by enemy radar which can identify the location of surface-to-air missiles.
From the smh.com.au
It is equipped with radar to search for water near the Moon's poles and spectrometers to map the distribution of minerals on the lunar surface.