How to write a query for picking 20 items from six tables with two conditions
Finally i made the query.

SELECT can.date_created,jobo.title,can.first_name,can.phone_cell,can.email1,can.current_employer,comp.name,canstatus.short_description,can.notes,can.city,jobo.city,extra.TotalExperience,extra.RelevantExperience,can.current_pay,can.desired_pay,extra.Noticeperiod,extra.Education,can.candidate_id
FROM candidate AS can 
LEFT JOIN candidate_joborder AS canjob 
ON can.candidate_id = canjob.candidate_id 
LEFT JOIN joborder AS jobo 
ON jobo.joborder_id = canjob.joborder_id 
LEFT JOIN company AS comp 
ON comp.company_id = jobo.company_id 
LEFT JOIN candidate_joborder_status canstatus 
ON canjob.status = canstatus.candidate_joborder_status_id 
LEFT JOIN ( 
 SELECT T.data_item_id, 
    MAX(CASE WHEN T.field_name = 'Education' THEN value END) AS Education,    
    MAX(CASE WHEN T.field_name = 'Contract or Permanent' THEN value END) AS ContractOrPermanent, 
    MAX(CASE WHEN T.field_name = 'Notice period' THEN value END) AS Noticeperiod, 
    MAX(CASE WHEN T.field_name = 'Total Experience' THEN value END) AS TotalExperience, 
    MAX(CASE WHEN T.field_name = 'Relevant Experience' THEN value END) AS RelevantExperience FROM extra_field AS T 
GROUP BY
    T.data_item_id) extra 
ON extra.data_item_id = can.candidate_id
WHERE can.entered_by =$user_id can.date_created LIKE '$date%'"


Thank you for every one who helped me