Hi hwayoungjun,
Thanks for using Syncfusion products.
Currently, support for displaying axis labels (labels that are not overlapping with any other label) in multiple lines is not available. Thank you for helping us define this feature. We have added it to our feature request list, and it will be available in any of our upcoming release .
To display a overlapping label in multiple lines, we can set labelIntersectAction property of axis to wrapbyword or multiplerows. We have prepared a simple example in the following link
Please let us know if you have any concern.
Regards,
Anand