如图所示，有两个重叠的正方形（150 y轴），我想分别显示它们，我该怎么做？

下面是代码方块项目符号：

var diaGraph = new AmCharts.AmGraph();
    diaGraph.valueAxis = bpValueAxis;
    diaGraph.valueField = "diastolic";
    diaGraph.balloonText = "DIA:[[diastolic]] "+uom+"<br><p style='font-size:9px;max-width:300px; word-wrap: break-word;'>[[alert_text]]</p>";
    diaGraph.colorField = "bullet_color";
    diaGraph.lineColor = "#808080";
    diaGraph.bullet = "square";
    chartBP.addGraph(diaGraph);