Filtering formulated cells

Hello! 

In my excel, on sheet 1 I have multiple formulated cells pulling data from 5 different sheets. In column A of the formulated cells, I want to filter the data being pulled from A to Z. When I filter though some of the data disappears and/or shows empty cells in between different cells with data in them. Is there a way to fix this so I can filter my column A and it shows all my data and in alphabetical form? 

Thanks!