SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '', 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    4078, 5006, 4103, 4104, 4106, 4105, 4107
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "product_id"],
      "key": "product_id",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 7,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (4078,5006,4103,4104,4106,4105,4107)",
      "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text
4078 <p>Replacement foam plugs. Noise reduction = 24dB Pack of 50. For RLN6230A/RLN6231A. </p> CP200 Headset, SL300 Headset, CP200XLS Headset, CP200d Headset, XPR6100 Headset, XPR6350 Headset, XPR6550 Headset, XPR6380 Headset, XPR6580 Headset, XPR7350 Headset, XPR7380 Headset, XPR7550 Headset, XPR7580 Headset, APX1000 Headset, APX3000 Headset, APX4000 Headset, APX6000 Headset, APX7000 Headset, APX600XE Headset, APX7000XE Headsets/Lapel Mics/Surveillance Kits
4103 <p>Swivel earpiece with in-line PTT for TLK100, TLK110, SL300, SL7550, SL7580, SL7590 (SL7000e Series).</p> SL300 Headset, Headsets/Lapel Mics/Surveillance Kits, SL300, SL-300, TLK100, TLK-100, TLK 100, 7189, PMLN-7189
4104 SL300 Headset, SL7550IS Headsets/Lapel Mics/Surveillance Kits, TLK100
4105 SL300 Headset, Headsets/Lapel Mics/Surveillance Kits, TLK100
4106 SL300 Headset, Headsets/Lapel Mics/Surveillance Kits, TLK100, SL300
4107 SL300 Headset, Headsets/Lapel Mics/Surveillance Kits, SL300, SL-300, TLK100, TLK 100, TLK-100
5006 <p>Low noise kit with Quick Disconnect translucent tube and clear rubber ear tip.</p>