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 (
    24996, 25008, 21386, 21623, 24830, 24144, 
    25095, 19725, 22548, 23544, 22290, 
    22291, 24832, 24751, 19937, 20472, 
    20381, 21222, 23686
  ) 
  AND pfv.product_id IN (
    49164, 49230, 1894, 23152, 47631, 49873, 
    6357, 41345, 35279, 25318, 47597, 47084, 
    5787, 3866, 18608, 2139, 42255
  ) 
  AND pfv.lang_code = 'vi'

Query time 0.02918

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": 346,
          "filtered": 0.941442728,
          "attached_condition": "pfv.feature_id in (24996,25008,21386,21623,24830,24144,25095,19725,22548,23544,22290,22291,24832,24751,19937,20472,20381,21222,23686) and pfv.product_id in (49164,49230,1894,23152,47631,49873,6357,41345,35279,25318,47597,47084,5787,3866,18608,2139,42255) 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'"
        }
      }
    ]
  }
}