SELECT 
  * 
FROM 
  cscart_product_options_inventory 
WHERE 
  product_id = 522 
  AND combination_hash = '2753953244'

Query time 0.00022

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_options_inventory const PRIMARY,pc PRIMARY 4 const 1

Result

product_id product_code combination_hash combination amount temp position price weight min_qty max_qty qty_step list_qty_count aval_status
522 BUD-CW50-05-26 2753953244 753_16331_752_16328_1359_24265 0.00 N 1 9.97 24000.00 0 0 0 0 10