Nested su_box

I want to make nested boxes but when I do
[su_box title="title with spaces"]
some text
[_su_box title="title with spaces 2" box_color="#ff0000"]
some text
[_/su_box]
some text
[/su_box]
it does not work: https://s22.postimg.org/ksvybreap/image.png

[su_box title="title with spaces"]
some text
[_su_box title="title with spaces 2" box_color="#ff0000"]
some text
[__/su_box]
some text
[/su_box]
(double _ in line 5)
does: https://s22.postimg.org/rkmdem3a9/image.png

And:

[su_box title="title with spaces"]
some text
[_su_box title=title with spaces 2 box_color=#ff0000]
some text
[__/su_box]
some text
[/su_box]
(no ” in line 3)
does: https://s22.postimg.org/holaeyxi9/image.png

But I need all the text in title, how to do this?

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