You need to keep them snooping around your fishing area
Among the most perceptive freshwater fish that swim, common carp can be quickly conditioned to show up when you chum with corn.
The trick is to chum at the same time every day for three or four days so the fish will be waiting for you (if you change the routine and show up at a different time to fish, however, they often won’t be there).
When you first arrive, throw a few handfuls of corn into the area you plan to target, then periodically sweeten the fringes as you fish. The trick is to keep the carp snooping around your fishing area like children on an Easter egg hunt, rather than allow them to quickly eat up everything and move on.