Need help with xpath_query for importxml in Google Sheets

The IMPORTXML formula for Google Sheets is "=IMPORTXML(Url, xpath_query)".For the webpage https://gocollect.com/comic/iron-man-282, I've been trying to extract the data under "Preview Grades", specifically the FMV data per grade. I don't know what I'm doing wrong, but I can't figure out the "xpath_query" to that data. For example, that data won't return using =importxml("https://gocollect.com/comic/iron-man-282","//div"). I also tried =importxml("https://gocollect.com/comic/iron-man-282","div[@class='col-span-4']") but that doesn't return anything. Any help with xpath_query to the data I want would be appreciated!