SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    510, 518, 395, 384, 371, 279, 405, 280, 
    372, 410, 394, 884, 406, 894
  )

Query time 0.00033

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_categories range parent parent 3 21 Using index condition

Result

category_id parent_id
510 280
518 280
371 280
372 280
406 280
894 280
279 384
405 384
410 384
884 384
395 394