Advanced search also not capable filter searching blank remarks in any column

Advanced search also not capable filter searching blank remarks in any column. Basic Filter is already not working well. Now Advance search is also not upto the expectations even though followed the step by step adding filters and saving again and again. Why it is so complication to do basic filters? Just Assigned to XYZ having All leads from Level 1,2,3,4. So simple Basic search. Please help to resolve this at the earliest