Zhao Hai took note of his surroundings. He was actually waiting for the nanomachines 'report. From the moment he realized they could be attacked, Zhao Hai had already released the nanomachine Wei Tong to check the surroundings. However, the other party was a little far away from them, so they didn't manage to send back any useful information.
The only reason Zhao Hai was able to find that person was all thanks to the nanomachines. However, as soon as the person was discovered, he immediately turned around and ran away. He was extremely alert, so Zhao Hai had no choice but to have the nanomachines expand the search area.