SELECT 
  pfv.variant_id, 
  pfv.position, 
  pfvd.variant 
FROM 
  cscart_product_feature_variants AS pfv 
  INNER JOIN cscart_product_feature_variant_descriptions AS pfvd ON pfv.variant_id = pfvd.variant_id 
  AND pfvd.lang_code = 'vi' 
WHERE 
  pfv.variant_id IN (
    70759, 71164, 71163, 71162, 71161, 71160, 
    71159, 71158, 71165, 71172, 71171, 
    71170, 71169, 71168, 71167, 71166, 
    71173, 71549, 71680, 71681, 73140, 
    73139, 73138, 73529, 73528, 73585, 
    73584, 74219, 74486, 74487, 74485, 
    74986, 74985, 74984, 74983, 74987, 
    76827, 78814, 78813, 78812, 78811, 
    78810, 78809, 78808, 78807, 78806, 
    78805, 78815, 79244, 79242, 79243, 
    79229, 79231, 79230, 81479, 81480, 
    81996, 81998, 82000, 81999, 81997, 
    82766, 82757, 82767, 82768, 82769, 
    82770, 82771, 82772, 82773, 82774, 
    82758, 82759, 82760, 82761, 82763, 
    82764, 82765, 83392, 83399, 83400, 
    83401, 83402, 83403, 83404, 83405, 
    83393, 83394, 83395, 83396, 83397, 
    83398, 86166, 86167, 86327, 86326, 
    86840, 86841, 87006, 87007, 87008, 
    87009, 87010, 87892, 87893
  )

Query time 0.02952

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "pfv",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["variant_id"],
          "rows": 105,
          "filtered": 100,
          "index_condition": "pfv.variant_id in (70759,71164,71163,71162,71161,71160,71159,71158,71165,71172,71171,71170,71169,71168,71167,71166,71173,71549,71680,71681,73140,73139,73138,73529,73528,73585,73584,74219,74486,74487,74485,74986,74985,74984,74983,74987,76827,78814,78813,78812,78811,78810,78809,78808,78807,78806,78805,78815,79244,79242,79243,79229,79231,79230,81479,81480,81996,81998,82000,81999,81997,82766,82757,82767,82768,82769,82770,82771,82772,82773,82774,82758,82759,82760,82761,82763,82764,82765,83392,83399,83400,83401,83402,83403,83404,83405,83393,83394,83395,83396,83397,83398,86166,86167,86327,86326,86840,86841,87006,87007,87008,87009,87010,87892,87893)"
        }
      },
      {
        "table": {
          "table_name": "pfvd",
          "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": "pfvd.lang_code = 'vi'"
        }
      }
    ]
  }
}