Custom URLs in Custom Search Results

You can get close to what you want by using the template_redirect hook.

function my_custom_search_url_rewrite() {
  if ( is_search() && ! empty( $_GET['s'] ) ) {
    wp_redirect( home_url( "/search/" ) . urlencode( get_query_var( 's' ) ) );
    exit();
  } 
}
add_action( 'template_redirect', 'my_custom_search_url_rewrite' );

Then you can use a URL like http://domain.com/search/category+location/.

If you then want to change search into find you could use the search_rewrite_rules filter like this.

function my_custom_search_url( $search_rewrite ) {
  if( !is_array( $search_rewrite ) ) { 
    return $search_rewrite;
  }

  $new_array = array();

  foreach( $search_rewrite as $pattern => $s_query_string ) {
    $new_array[ str_replace( 'search/', 'find/', $pattern ) ] = $s_query_string;
  }

  $search_rewrite = $new_array;

  unset( $new_array );

  return $search_rewrite;
}
add_filter("search_rewrite_rules", "my_custom_search_url");

Then you can use a URL like http://domain.com/find/category+location/.

Note: Remember to flush or re-save your permalinks.

I’m sure, with some more tinkering, you could get a bit closer to what you asked for but this is as close I’ve got so far.

EDIT:
Sorry forgot to mention… if you use the function for the search_rewrite_rules filter you’ll need to change the my_custom_url_rewrite function to this.

function my_custom_search_url_rewrite() {
  if ( is_search() && ! empty( $_GET['s'] ) ) {
    wp_redirect( home_url( "/find/" ) . urlencode( get_query_var( 's' ) ) );
    exit();
  } 
}
add_action( 'template_redirect', 'my_custom_search_url_rewrite' );