The UT offers minors during the second semester, for students who couldn't during the first semester. Be aware that the amount of minors that are being offered, is a lot smaller than during the first semester.
Down below you can find a link to an overview of the minors of the second semester (course year 2017-2018). During course year 2018-2019 the offer will most likely be more or less the same, but will be published later this year (around autumn). In a few days you can find in the tool of options which minors you are allowed to follow. For now take a look at the matrix.
Students who are taking a minor of the second semester of course year 2017-2018 do still need to register for the module of the minor.