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 (
    627, 927, 864, 470, 916, 638, 606, 560, 
    625, 1018, 787, 476, 652, 1128, 884, 
    918, 1122, 1125, 1126, 473, 513, 1094, 
    398, 412, 422, 443, 406, 455, 917, 888, 
    618, 636, 553, 429, 901, 459, 410, 552, 
    551, 842, 1123, 912, 910, 911, 913, 914, 
    915, 967, 417, 433, 580, 514, 471, 654, 
    263, 1037, 574, 495, 813, 1086, 844, 
    756, 755, 434, 863, 220, 823, 610, 867, 
    858, 635, 1044, 579, 578, 1127, 1042, 
    868, 517, 938, 946, 456, 559, 542, 407, 
    866, 515, 561, 491, 493, 573, 651, 562, 
    435, 523, 650, 583
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00245

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": 96,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (627,927,864,470,916,638,606,560,625,1018,787,476,652,1128,884,918,1122,1125,1126,473,513,1094,398,412,422,443,406,455,917,888,618,636,553,429,901,459,410,552,551,842,1123,912,910,911,913,914,915,967,417,433,580,514,471,654,263,1037,574,495,813,1086,844,756,755,434,863,220,823,610,867,858,635,1044,579,578,1127,1042,868,517,938,946,456,559,542,407,866,515,561,491,493,573,651,562,435,523,650,583) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text unit_name
220
263
398
406
407
410
412
417
422
429
433
434
435
443
455
456
459
470
471
473
476
491
493
495
513
514
515
517
523
542
551
552
553
559
560
561
562
573
574
578
579
580
583
606
610
618
625
627
635
636
638
650
651
652
654
755
756
787
813
823
842
844
858
863
864
866
867
868
884
888
901
910
911
912
913
914
915
916
917
918
927
938
946
967
1018
1037
1042
1044
1086
1094
1122
1123
1125
1126
1127
1128