SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    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, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    403, 1414, 151, 57, 58, 29, 1947, 683, 
    1377, 1166, 358, 1167, 708, 1177, 1195, 
    1208, 1178, 1849, 1846, 1848, 1847, 
    1171, 1322, 1448, 789, 1375, 1230, 1227, 
    1770, 1769, 1420, 77, 1449, 1235, 1442, 
    1958, 67, 1252, 803, 1169, 1712, 1759, 
    1341, 1592, 1474, 1733, 1002, 1930
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00156

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "product_id"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["product_id", "lang_code"],
      "rows": 48,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (403,1414,151,57,58,29,1947,683,1377,1166,358,1167,708,1177,1195,1208,1178,1849,1846,1848,1847,1171,1322,1448,789,1375,1230,1227,1770,1769,1420,77,1449,1235,1442,1958,67,1252,803,1169,1712,1759,1341,1592,1474,1733,1002,1930) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text unit_name
29
57
58
67
77
151
358
403
683
708
789
803
1002
1166
1167
1169
1171
1177
1178
1195
1208
1227
1230
1235
1252
1322
1341
1375
1377
1414
1420
1442
1448
1449
1474
1592
1712
1733
1759
1769
1770
1846
1847
1848
1849
1930
1947
1958