SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  IF(
    shared_descr.product_id IS NOT NULL, 
    shared_descr.product, descr1.product
  ) as product, 
  companies.company as company_name, 
  products.product_type, 
  products.parent_product_id 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'en' 
  LEFT JOIN cscart_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  LEFT JOIN cscart_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN cscart_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN cscart_categories ON cscart_categories.category_id = products_categories.category_id 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  AND cscart_categories.storefront_id IN (0, 1) 
  LEFT JOIN cscart_ult_product_descriptions shared_descr ON shared_descr.product_id = products.product_id 
  AND shared_descr.company_id = 1 
  AND shared_descr.lang_code = 'en' 
  LEFT JOIN cscart_product_restricted_countries AS prc ON prc.product_id = products.product_id 
  AND prc.country_code = 'US' 
WHERE 
  1 
  AND companies.status IN ('A') 
  AND (
    products.usergroup_ids = '' 
    OR FIND_IN_SET(0, products.usergroup_ids) 
    OR FIND_IN_SET(1, products.usergroup_ids)
  ) 
  AND products.status IN ('A') 
  AND prices.usergroup_id IN (0, 0, 1) 
  AND (
    (
      1 
      AND products.product_id IN (
        45215, 45216, 45217, 45218, 45219, 45220, 
        45221, 45222, 45223, 45224, 45225, 
        45226, 45227, 45228, 45229, 45230, 
        45231, 45232, 45233, 45234, 45235, 
        45236, 45237, 45238, 45239
      )
    ) 
    AND companies.status IN ('A') 
    AND prices.usergroup_id IN (0, 0, 1)
  ) 
  AND (
    products.available_worldwide = 'Y' 
    OR prc.country_code IS NULL
  ) 
GROUP BY 
  products.product_id 
ORDER BY 
  products.timestamp desc, 
  products.product_id desc, 
  products.product_id ASC

Query time 0.00145

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE companies ALL PRIMARY 1 Using where; Using temporary; Using filesort
1 SIMPLE products range PRIMARY,status PRIMARY 3 25 Using where; Using join buffer (flat, BNL join)
1 SIMPLE shared_descr eq_ref PRIMARY,product_id,company_id PRIMARY 13 toolboxdigitalshop_dev.products.product_id,const,const 1 Using where
1 SIMPLE prc eq_ref PRIMARY PRIMARY 9 toolboxdigitalshop_dev.products.product_id,const 1 Using where; Using index
1 SIMPLE prices ref usergroup,product_id,lower_limit,usergroup_id usergroup 3 toolboxdigitalshop_dev.products.product_id 1 Using where; Using index
1 SIMPLE descr1 eq_ref PRIMARY,product_id PRIMARY 9 toolboxdigitalshop_dev.products.product_id,const 1 Using where
1 SIMPLE products_categories ref PRIMARY,pt pt 3 toolboxdigitalshop_dev.products.product_id 1 Using index
1 SIMPLE cscart_categories eq_ref PRIMARY,c_status,p_category_id PRIMARY 3 toolboxdigitalshop_dev.products_categories.category_id 1 Using where

Result

product_id product company_name product_type parent_product_id
45239 Booming Track (Original Mix) Toolbox Digital Shop P 0
45238 Walking On The Moon (Original Mix) Toolbox Digital Shop P 0
45237 New Generation (Original Mix) Toolbox Digital Shop P 0
45236 Bad Ass Bass (Original Mix) Toolbox Digital Shop P 0
45235 Is It Any Wonder? (Original Mix) Toolbox Digital Shop P 0
45234 From Me (Original Mix) Toolbox Digital Shop P 0
45233 Nothings Gonna Change (Original Mix) Toolbox Digital Shop P 0
45232 SFX (Original Mix) Toolbox Digital Shop P 0
45231 I Missed You (Original Mix) Toolbox Digital Shop P 0
45230 Let's Hear It (Original Mix) Toolbox Digital Shop P 0
45229 #Evilution (Original Mix) Toolbox Digital Shop P 0
45228 Givin' It All I Got (Original Mix) Toolbox Digital Shop P 0
45227 Aura (Original Mix) Toolbox Digital Shop P 0
45226 Master Xploder (Partyraiser Remix) Toolbox Digital Shop P 0
45225 Now I Let Them Go (Original Mix) Toolbox Digital Shop P 0
45224 Rhino Spunk (Original Mix) Toolbox Digital Shop P 0
45223 Catchit (DJ Edit) Toolbox Digital Shop P 0
45222 Never Change (Original Mix) Toolbox Digital Shop P 0
45221 True (Original Mix) Toolbox Digital Shop P 0
45220 Cool Kids (Original Mix) Toolbox Digital Shop P 0
45219 Little Fantasy (Original Mix) Toolbox Digital Shop P 0
45218 DX2R (SRB Remix) Toolbox Digital Shop P 0
45217 Conquer (Original Mix) Toolbox Digital Shop P 0
45216 Brainstabber (Original Mix) Toolbox Digital Shop P 0
45215 Blood, Sweat & Hardcore (The Beatkrusher Remix) Toolbox Digital Shop P 0