SELECT 
  * 
FROM 
  cscart_vd_vendors_relationships 
WHERE 
  brand_id = 160

Query time 0.00040

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
16442 160 661 2198 es
16441 160 663 2226 es
16440 160 649 1927 es
16439 160 648 1911 es
16438 160 654 2141 es
16437 160 654 2140 es
16436 160 647 1890 es
16435 160 662 2211 es
16434 160 660 2187 es
16433 160 658 2179 es
16432 160 652 2125 es
16431 160 652 2103 es
16430 160 652 2105 es
16429 160 652 2116 es
16428 160 646 1887 es
16427 160 653 2129 es