SELECT 
  b.*, 
  d.*, 
  c.* 
FROM 
  cscart_bm_blocks as b 
  LEFT JOIN cscart_bm_blocks_descriptions as d ON b.block_id = d.block_id 
  LEFT JOIN cscart_bm_blocks_content as c ON b.block_id = c.block_id 
  AND d.lang_code = c.lang_code 
WHERE 
  b.block_id = 56 
  AND d.lang_code = 'ja' 
  AND b.company_id = 1 
  AND (
    (
      c.object_id = 4 
      AND c.object_type like 'products'
    ) 
    OR (
      c.object_id = 0 
      AND c.object_type like ''
    )
  ) 
ORDER BY 
  snapping_id DESC 
LIMIT 
  1

Query time 0.00060

JSON explain

{
  "query_block": {
    "select_id": 1,
    "ordering_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "b",
            "access_type": "const",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "block_id"
            ],
            "key_length": "4",
            "ref": [
              "const"
            ],
            "rows": 1,
            "filtered": 100
          }
        },
        {
          "table": {
            "table_name": "d",
            "access_type": "const",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "block_id",
              "lang_code"
            ],
            "key_length": "10",
            "ref": [
              "const",
              "const"
            ],
            "rows": 1,
            "filtered": 100
          }
        },
        {
          "table": {
            "table_name": "c",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "block_id"
            ],
            "key_length": "4",
            "ref": [
              "const"
            ],
            "rows": 2,
            "filtered": 100,
            "attached_condition": "((`_testcscart`.`c`.`block_id` <=> 56) and ((`_testcscart`.`c`.`lang_code` = 'ja') and (((`_testcscart`.`c`.`object_id` = 4) and (`_testcscart`.`c`.`object_type` like 'products')) or ((`_testcscart`.`c`.`object_id` = 0) and (`_testcscart`.`c`.`object_type` like '')))))"
          }
        }
      ]
    }
  }
}