Android : ทำแอนดรอยด์ค้นหาหลายตารางติดปัญหา error ช่วยบอกวิธีแก้ปัญหาหน่อยครับ

<?php
	$objConnect = mysql_connect("localhost","root","12345");
	$objDB = mysql_select_db("db_conn");
	


	$strSQL = "SELECT * FROM plant WHERE 
	(pnt_id LIKE '%".$strKeyword."%' 
		OR family_id LIKE '%".$strKeyword."%'
	 OR pnt_date LIKE '%".$strKeyword."%'
	OR pnt_comm_name LIKE '%".$strKeyword."%'
	 OR pnt_sci_name LIKE '%".$strKeyword."%'
	 OR pnt_vernac_name LIKE '%".$strKeyword."%'
	 OR pnt_synonym_name LIKE '%".$strKeyword."%'
	 OR pnt_info LIKE '%".$strKeyword."%'
	 OR pnt_benefit LIKE '%".$strKeyword."%') UNION
	SELECT * FROM tree WHERE 
	(tree_coor LIKE '%".$strKeyword."%' )";

	
	$objQuery = mysql_query($strSQL);
	$intNumField = mysql_num_fields($objQuery);
	$resultArray = array();
	while($obResult = mysql_fetch_array($objQuery))
	{
		$arrCol = array();
		for($i=0;$i<$intNumField;$i++)
		{
			$arrCol[mysql_field_name($objQuery,$i)] = $obResult[$i];
		}
		array_push($resultArray,$arrCol);
	}
	echo mysql_error();
	mysql_close($objConnect);
	
	echo json_encode($resultArray);
?>