Everything in my svg image is not resized correctly

I have an svg file that I open in illustrator. It is too big so I resize it by selecting the image and dragging one of the corners while pressing shift. It resizes, but some parts of the image is not resized correctly. Maybe it has to do with the image from the beginning (which is created by a visualizing software) or am I doing something wrong?

I can select the parts manually and resize them if they are few, but most often they are so many and not easily selected. 

As you can see in the file, the lines between the blocks and the text are not resized correctly, at least not all of them.

Thanks in advance!