Stored Procedure doesn't return any result as output but query works fine
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Why this stored procedure doesn't return any result

    CREATE PROCEDURE `sp_location_selectAllByTermAutoComplete`(
    IN _term VARCHAR(99))
    BEGIN
    
    	SELECT
    		`title` AS `value`,
    		`keyword` AS `label`,
    		`city_id`,
    		`id` AS `locationtitle_id`
    	FROM `locationtitle`
    	WHERE
    		MATCH(`keyword`) AGAINST(_term  IN BOOLEAN MODE)
    	ORDER BY MATCH(`keyword`) AGAINST(_term  IN BOOLEAN MODE) DESC
    	LIMIT 0, 10
    ;END//

But this one returned

    	SELECT
    		`title` AS `value`,
    		`keyword` AS `label`,
    		`city_id`,
    		`id` AS `locationtitle_id`
    	FROM `locationtitle`
    	WHERE
    		MATCH(`keyword`) AGAINST('+NEW*'  IN BOOLEAN MODE)
    	ORDER BY MATCH(`keyword`) AGAINST('+NEW*'  IN BOOLEAN MODE) DESC
    	LIMIT 0, 10

Both of the input parameters are same as other.
I have other stored procedure and they works fine.
I'm using `PDO` to execute my stored procedure.
I never used `OUT` in my stored procedure and no experience how to use it.