Thank you.. :)
You can access all properties of dataPoint/dataSeries including label. Upon any mouse event you get dataSeries and dataPoint inside the parameter e – which is passed to the event handler function. Once you have the handle to dataPoint, you can access all the properties inside dataPoint
ex: e.dataPoint.label
Checkout the documentation below
https://canvasjs.com/docs/charts/basics-of-creating-html5-chart/event-handling/