Where the tab stops are located depend on the program that is displaying the String with the tabs.
Many Text viewing programs have a setting that allows you to specify what columns the tab stops are located in.
The problem you are having looks like one of the Strings extends past the tab location and pushes the data to a further tab column than with a shorter String. If you can determine what columns the tab stops are located in, you should be able to add an extra tab character to the shorter String.