SELECT 
  * 
FROM 
  cscart_vd_vendors_relationships 
WHERE 
  brand_id = 181

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_vd_vendors_relationships",
          "access_type": "ref",
          "possible_keys": ["brand_id"],
          "key": "brand_id",
          "key_length": "4",
          "used_key_parts": ["brand_id"],
          "ref": ["const"],
          "rows": 17,
          "filtered": 100
        }
      }
    ]
  }
}

Result

id brand_id feature_id variant_id lang_code
13535 181 661 2198 es
13534 181 649 1924 es
13533 181 648 1896 es
13532 181 654 2140 es
13531 181 654 2137 es
13530 181 647 1890 es
13529 181 662 2219 es
13528 181 662 2212 es
13527 181 662 2205 es
13526 181 660 2188 es
13525 181 658 2186 es
13524 181 652 2107 es
13523 181 652 2106 es
13522 181 652 2123 es
13521 181 652 2116 es
13520 181 646 1887 es
13519 181 653 2130 es