Disable search form in nav from collapsing
You can change your markup using the page.tpl.php


Copy the page.tpl.php file from /bootstrap/templates/system to your theme.
Edit the page.tpl.php that you've copied.
Move the line 108 - 110 below / above the navbar-collapse collapse div.





Create a new div.
Put the code from line 108 - 110 into the new div.
Save
The changes should be like the screenshot below.





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