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 (
    1368, 1321, 1367, 1366, 1365, 1364, 1363, 
    1362, 1361, 1360, 1359, 1358, 1357, 
    1356, 1355, 1354, 1353, 1352, 1351, 
    1350, 1349, 1348, 1346, 1036, 1345, 
    1335, 1344, 1343, 1336, 1334, 1333, 
    1332, 1331, 1329, 1328, 1327, 1326, 
    1325, 1323, 1322, 1320, 1300, 1301, 
    1302, 1303, 1312, 1304, 1305
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00143

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 (1368,1321,1367,1366,1365,1364,1363,1362,1361,1360,1359,1358,1357,1356,1355,1354,1353,1352,1351,1350,1349,1348,1346,1036,1345,1335,1344,1343,1336,1334,1333,1332,1331,1329,1328,1327,1326,1325,1323,1322,1320,1300,1301,1302,1303,1312,1304,1305) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text unit_name
1036
1300
1301
1302
1303
1304
1305
1312
1320
1321
1322
1323
1325
1326
1327
1328
1329
1331
1332
1333
1334
1335
1336
1343
1344
1345
1346
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368