SELECT 
  pfv.feature_id, 
  pfv.product_id, 
  pfv.variant_id, 
  fv.position, 
  fvd.variant 
FROM 
  cscart_product_features_values AS pfv 
  INNER JOIN cscart_product_feature_variants AS fv ON pfv.feature_id = fv.feature_id 
  AND pfv.variant_id = fv.variant_id 
  INNER JOIN cscart_product_feature_variant_descriptions AS fvd ON pfv.variant_id = fvd.variant_id 
  AND fvd.lang_code = 'vi' 
WHERE 
  pfv.feature_id IN (
    24571, 24839, 24570, 24797, 24769, 24864, 
    24825, 23645, 24870, 24770
  ) 
  AND pfv.product_id IN (
    44951, 47650, 44751, 47427, 47256, 47975, 
    47570, 35697, 48026, 47257
  ) 
  AND pfv.lang_code = 'vi'

Query time 0.02516

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "pfv",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "variant_id",
            "lang_code",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "PRIMARY",
          "key_length": "6",
          "used_key_parts": ["feature_id", "product_id"],
          "rows": 105,
          "filtered": 0.02386074,
          "attached_condition": "pfv.feature_id in (24571,24839,24570,24797,24769,24864,24825,23645,24870,24770) and pfv.product_id in (44951,47650,44751,47427,47256,47975,47570,35697,48026,47257) and pfv.lang_code = 'vi'",
          "using_index": true
        }
      },
      {
        "table": {
          "table_name": "fv",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "feature_id"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["variant_id"],
          "ref": ["dev_db.pfv.variant_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "fv.feature_id = pfv.feature_id"
        }
      },
      {
        "table": {
          "table_name": "fvd",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["variant_id", "lang_code"],
          "ref": ["dev_db.pfv.variant_id", "const"],
          "rows": 1,
          "filtered": 100,
          "index_condition": "fvd.lang_code = 'vi'"
        }
      }
    ]
  }
}

Result

feature_id product_id variant_id position variant
23645 35697 81987 1 Moony 1
24570 44751 85760 1 Ngang
24571 44951 85762 1 Ngang
24769 47256 86388 1 Màu đen
24770 47257 86391 1 Trắng be
24797 47427 86504 1 Màu xanh lục
24825 47570 86575 1 Gối thiền
24839 47650 86631 1 Size S cho nữ
24864 47975 86703 1 be grateful
24870 48026 86733 1 be grateful