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SELECT 
  cscart_vendor_plan_descriptions.*, 
  cscart_vendor_plans.*, 
  manual_rating.rating AS manual_rating 
FROM 
  cscart_vendor_plans 
  LEFT JOIN cscart_vendor_plan_descriptions ON cscart_vendor_plan_descriptions.plan_id = cscart_vendor_plans.plan_id 
  AND cscart_vendor_plan_descriptions.lang_code = 'tr' 
  LEFT JOIN cscart_manual_rating AS manual_rating ON manual_rating.object_id = cscart_vendor_plans.plan_id 
  AND manual_rating.object_type = 'vendor_plan' 
WHERE 
  (
    status IN('A')
  ) 
  AND (
    FIND_IN_SET(1, storefronts) 
    OR storefronts IS NULL 
    OR storefronts = ''
  ) 
ORDER BY 
  position asc

Query time 0.00164

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	cscart_vendor_plans	ALL					5	Using where; Using filesort
1	SIMPLE	cscart_vendor_plan_descriptions	eq_ref	PRIMARY	PRIMARY	10	hobilifedt.cscart_vendor_plans.plan_id,const	1	Using where
1	SIMPLE	manual_rating	eq_ref	PRIMARY	PRIMARY	102	hobilifedt.cscart_vendor_plans.plan_id,const	1	Using where

Result

plan_id	lang_code	plan	status	position	is_default	price	periodicity	commission	products_limit	revenue_limit	vendor_store	manual_rating
2	tr	Bronze	A	10	0	0.00	month	20.00	25	500.00	0
1	tr	Silver	A	20	0	100.00	month	10.00	1000	1000.00	1
3	tr	Gold	A	30	1	250.00	month	5.00	10000	10000.00	1
4	tr	Platinum	A	40	0	0.00	onetime	10.00	100000	0.00	1	0