Grid of amazon images not showing full rows

Hi,
I want to showcase my articles in a grid , that’s why I added the shortcodes one after the other in the wp code, each in a new row.
However, when I look at them in different browsers and on different screens, I see some rows that are fully filled with four items, whereas other rows are not entirely filled and only show one, two or three items.
I think I found out why, but I don’t know how to change it:
As you can see on this page (https://www.michaelaurban.com/en/equipment/) some Amazon descriptions take up only two lines, others three. Whenever a new row starts, it looks like the first product in that row is always placed one column to the right of last of the three-lined description item from the row above.
What part of the coding do I need to change to show a nicely looking grid?
Thanks a lot,
Michaela