You mean the 400km range? Why can't? the object is airborne (AWACS, P-8)
View attachment 409634
https://en.wikipedia.org/wiki/Type_346_Radar
Radar Horizon + Atmosphere + Environmental Noise
Of course in "U.S. fanboy physics" these do not apply to U.S. made radars and they can detect and identify the tiniest Chinese periscope popping out of the water at maximum theoretical range with zero clutter.