WP Editor will automatically remove the carriage return line, the article is squeezed into a piece, there is no good solution

WP Editor will automatically remove the carriage return line, the article is squeezed to a piece, what is the best way to solve?
WP 4.1 version, in the editor, the layout is a newline, but after the release, the front desk saw the line is not, how to solve this problem?
If you manually add a carriage return in the text mode
Yes, but if you switch to Rich text mode, edit, modify,
It's automatically removed.
------to solve the idea----------------------
Using the NL2BR function
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Nl2br
That text wrapping is just a line in the HTML code that shows up as a space

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