How can I increase the number of trace points in moveit?

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When I use moveit！ to form a trajectory, I can subscribe follow_joint_trajectory/goal to see the information of various points in the trajectory. However, I realize that the number of these points is relatively small, and a complete trajectory cannot be obtained. Can I set some parameters to increase the number of midpoints of trajectories released by follow_joint_trajectory/goal? If only algorithms can be used, what algorithm can increase the number of points while ensuring continuity of velocity?