同声

simultaneous; in chorus; in unison; synchronize; dub; speak at the same time

相应

corresponding; relevant; matching; reciprocal; commensurate; equivalent; act in response; match; parallel; correspond; work in concert with; in proportion; correspondingly; accordingly

同气相求

like attracts like; birds of a feather flock together; people of the same kind seek each other out; kindred spirits seek each other