You can archive this using the child-theme feature and changing the link on the html button.
First make sure you've created a child-theme... You can do this from the admin under Design - Themes.
Create a folder within your child theme called 'local_module', and create a file 'local_module.php' inside that folder.
Copy the content of view file 'extensions/local_module/views/local_module.php' into a newly created file.
You should have the same file content in 'your-child-theme/local_module/local_module.php' and 'extensions/local_module/views/local_module.php'
Now inside 'your-child-theme/local_module/local_module.php', find the if statement block on line 11
It should look like this,
[php]<?php if ($location_search_mode === 'multi') { ?>
<form id="location-form" method="POST" action="<?php echo $local_action; ?>" role="form">
<div class="input-group postcode-group">
<input type="text" id="search-query" class="form-control text-center postcode-control input-lg" name="search_query" placeholder="<?php echo lang('label_search_query'); ?>" value="<?php echo $search_query; ?>">
<a id="search" class="input-group-addon btn btn-primary" onclick="searchLocal()"><?php echo lang('text_find'); ?></a>
</div>
</form>
<?php } else { ?>
<a class="btn btn-block btn-primary" href="<?php echo $single_location_url; ?>"><?php echo lang('text_find'); ?></a>
<?php } ?>[/php]
replace it with
<a class="btn btn-block btn-primary" href="<?php echo site_url('local/all'); ?>"><?php echo lang('text_find'); ?></a>
I hope it helps and clear enough.