Variables inside xpath in "XPATH" option of "GET_WEB_Value" command are not recognized

When using a variable inside the xpath option of "GET_WEB_VALUE", it's not recognized. However if it's used in the xpath when creating locator, it's recognized.

Below the value of variable "row_num=1" is not recognized when using in the xapth, however if using 1 directly in xpath, it works. The variable in the locator also works.

Using Variable:

When using Xpath with variable inside the locator:

When using xPath without variable: