SELECT 
  video_id, 
  product_id 
FROM 
  cscart_ab__video_gallery 
WHERE 
  product_id IN (
    1515, 1516, 1517, 1603, 1519, 1768, 1518, 
    1769
  )

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_ab__video_gallery",
      "access_type": "range",
      "possible_keys": ["product_id"],
      "key": "product_id",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 8,
      "filtered": 100,
      "attached_condition": "cscart_ab__video_gallery.product_id in (1515,1516,1517,1603,1519,1768,1518,1769)",
      "using_index": true
    }
  }
}