SELECT 
  bm_blocks.block_id, 
  bm_blocks.type, 
  bm_blocks.properties, 
  bm_blocks.company_id, 
  bm_blocks_content.content, 
  bm_blocks_descriptions.name, 
  abt__mv_vendor_blocks.status, 
  abt__mv_vendor_blocks.position 
FROM 
  cscart_bm_blocks AS bm_blocks 
  INNER JOIN cscart_bm_blocks_content AS bm_blocks_content ON bm_blocks_content.block_id = bm_blocks.block_id 
  AND bm_blocks_content.lang_code = 'vn' 
  AND bm_blocks_content.snapping_id = 0 
  AND bm_blocks_content.object_id = 0 
  AND bm_blocks_content.object_type = '' 
  INNER JOIN cscart_bm_blocks_descriptions AS bm_blocks_descriptions ON bm_blocks_descriptions.block_id = bm_blocks.block_id 
  AND bm_blocks_descriptions.lang_code = 'vn' 
  LEFT JOIN cscart_abt__ut2_mv_vendor_blocks abt__mv_vendor_blocks ON bm_blocks.block_id = abt__mv_vendor_blocks.block_id 
WHERE 
  bm_blocks.company_id = 3 
  AND abt__mv_vendor_blocks.block_id IS NOT NULL 
  AND abt__mv_vendor_blocks.status = 'A' 
GROUP BY 
  bm_blocks.block_id 
ORDER BY 
  abt__mv_vendor_blocks.position asc

Query time 0.00109

JSON explain

{
  "query_block": {
    "select_id": 1,
    "filesort": {
      "sort_key": "abt__mv_vendor_blocks.position",
      "temporary_table": {
        "nested_loop": [
          {
            "table": {
              "table_name": "abt__mv_vendor_blocks",
              "access_type": "ALL",
              "rows": 1,
              "filtered": 100,
              "attached_condition": "abt__mv_vendor_blocks.block_id is not null and abt__mv_vendor_blocks.`status` = 'A'"
            }
          },
          {
            "table": {
              "table_name": "bm_blocks",
              "access_type": "eq_ref",
              "possible_keys": ["PRIMARY"],
              "key": "PRIMARY",
              "key_length": "4",
              "used_key_parts": ["block_id"],
              "ref": ["v8.abt__mv_vendor_blocks.block_id"],
              "rows": 1,
              "filtered": 100,
              "index_condition": "bm_blocks.block_id = abt__mv_vendor_blocks.block_id",
              "attached_condition": "bm_blocks.company_id = 3"
            }
          },
          {
            "table": {
              "table_name": "bm_blocks_descriptions",
              "access_type": "eq_ref",
              "possible_keys": ["PRIMARY"],
              "key": "PRIMARY",
              "key_length": "10",
              "used_key_parts": ["block_id", "lang_code"],
              "ref": ["v8.abt__mv_vendor_blocks.block_id", "const"],
              "rows": 1,
              "filtered": 100,
              "index_condition": "bm_blocks_descriptions.block_id = bm_blocks.block_id and bm_blocks_descriptions.lang_code = 'vn'"
            }
          },
          {
            "table": {
              "table_name": "bm_blocks_content",
              "access_type": "eq_ref",
              "possible_keys": ["PRIMARY"],
              "key": "PRIMARY",
              "key_length": "212",
              "used_key_parts": [
                "block_id",
                "snapping_id",
                "lang_code",
                "object_id",
                "object_type"
              ],
              "ref": [
                "v8.abt__mv_vendor_blocks.block_id",
                "const",
                "const",
                "const",
                "const"
              ],
              "rows": 1,
              "filtered": 100,
              "index_condition": "bm_blocks_content.block_id = bm_blocks.block_id and bm_blocks_content.lang_code = 'vn' and bm_blocks_content.object_type = ''"
            }
          }
        ]
      }
    }
  }
}