How can I add a "Back to Search" link to user profiles?
You can do this wih a new module modifying the user profile view.

// Implements hook_user_view().
function MY_MODULE_user_view($account, $view_mode, $langcode) {
  $account-&gt;content['link'] = array(
    '#weight' =&gt; -10,
    0 =&gt; array(
      '#markup' =&gt; '&lt;a href="/VIEW_URI"&gt;Back to Search&lt;/a&gt;',
    ),
  );
}


Note: When adding a hook always remember to clear caches

If you also want to preserve the filter that the user has applied you can do so within your filter in the view by selecting 'remember the last selection' and selecting the roles that you want this for.