SELECT 
  video_id, 
  product_id 
FROM 
  cscart_ab__video_gallery 
WHERE 
  product_id IN (
    21085, 21086, 21087, 21088, 21089, 21090, 
    21091, 21092, 21093, 21094, 21095, 
    21096, 21097, 21098, 21099, 21100
  ) 
  AND status = "A"

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_ab__video_gallery",
      "access_type": "ref",
      "possible_keys": ["status", "product_id"],
      "key": "status",
      "key_length": "3",
      "used_key_parts": ["status"],
      "ref": ["const"],
      "rows": 1,
      "filtered": 100,
      "index_condition": "cscart_ab__video_gallery.`status` = 'A'",
      "attached_condition": "cscart_ab__video_gallery.product_id in (21085,21086,21087,21088,21089,21090,21091,21092,21093,21094,21095,21096,21097,21098,21099,21100)"
    }
  }
}