SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    10009, 10012, 10420, 10428, 10406, 10480, 
    10486, 10545, 10488, 10384, 10553, 
    10482, 10013, 10381, 10467, 10551, 
    10011, 10555, 10007, 10008, 10010, 
    10357, 10358, 10378
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00112

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "33.61"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "range",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "key": "usergroup",
        "used_key_parts": [
          "product_id",
          "usergroup_id",
          "lower_limit"
        ],
        "key_length": "9",
        "rows_examined_per_scan": 48,
        "rows_produced_per_join": 48,
        "filtered": "100.00",
        "index_condition": "((`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_prices`.`lower_limit` = 1) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_prices`.`product_id` in (10009,10012,10420,10428,10406,10480,10486,10545,10488,10384,10553,10482,10013,10381,10467,10551,10011,10555,10007,10008,10010,10357,10358,10378)) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_prices`.`usergroup_id` in (0,1)))",
        "cost_info": {
          "read_cost": "28.81",
          "eval_cost": "4.80",
          "prefix_cost": "33.61",
          "data_read_per_join": "1K"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ]
      }
    }
  }
}

Result

product_id price
10007 39000.00000000
10008 32000.00000000
10009 36000.00000000
10010 35000.00000000
10011 38000.00000000
10012 38000.00000000
10013 15000.00000000
10357 55000.00000000
10358 47750.00000000
10378 41500.00000000
10381 39000.00000000
10384 63250.00000000
10406 39000.00000000
10420 60000.00000000
10428 142000.00000000
10467 425000.00000000
10480 219750.00000000
10482 157000.00000000
10486 21250.00000000
10488 102250.00000000
10545 239000.00000000
10551 38000.00000000
10553 72000.00000000
10555 199750.00000000