Time Machine will backup everything on the Mac unless you specifically Exclude the files from being backed up. If the Documents and Photos folder are not being backed up, then someone placed them on a list of items to be Excluded from backups.
These folders will appear in the list of Excluded items.
Click the Time Machine "clock" icon at the top of the Mac's screen
Click Time Machine Preferences
Click on the Documents folder to highlight it, then click the - (minus) button at the bottom of the list to remove the Documents folder from Excluded items.
Time Machine will now back up the Documents folder on the next pass.
Do the same for the Photo folder and it wil be backed up on the next pass as well.