SELECT 
  * 
FROM 
  cscart_vd_vendors_relationships 
WHERE 
  brand_id = 95

Query time 0.00035

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": 12,
          "filtered": 100
        }
      }
    ]
  }
}

Result

id brand_id feature_id variant_id lang_code
1653 95 653 2128 es
1654 95 653 2129 es
1655 95 660 2188 es
1658 95 649 1925 es
1659 95 652 2116 es
1660 95 652 2119 es
1661 95 652 2103 es
1662 95 652 2124 es
1663 95 652 2110 es
1664 95 654 2140 es
1665 95 647 1889 es
5796 95 661 2198 es