Hey there,

It's better if I can just summarize what I have understood you to want, then implement those changes in my example.
You can then adapt them to what you have.

So, you would like to start off showing all records and having the check boxes unchecked.
After that you would like to filter the results according to what is checked.
For example, if the user checks "Samsung", only the Samsung phones should be shown.
If the user then checks "iPhone", Samsung and iPhone phones should be displayed.
If the user then removes unchecks all of the boxes, every record should be displayed.

Is that correct?