SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    103, 104, 105, 106, 107, 108, 109, 110, 
    111, 112, 113, 114, 115, 116, 117, 118, 
    119, 120, 121, 122, 123, 124, 125, 127, 
    129, 131, 132, 133, 134, 135, 136, 137
  )

Query time 0.00113

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 32,
          "filtered": 100,
          "index_condition": "cscart_products.product_id in (103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,127,129,131,132,133,134,135,136,137)"
        }
      }
    ]
  }
}