SELECT 
  * 
FROM 
  cscart_product_options_inventory 
WHERE 
  product_id = 9839 
  AND combination_hash = '2193468843'

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
9839 ODV-RFL-C01-1028S 2193468843 1160_21915_1159_21897_1155_21886 0.00 N 64 273.98 4.00 0 0 0 0 15