Exclamation [Q] could not find backup file saved internal SD Card

I have Galaxy S 4 I9500 and my problem is i could not find backup file saved internal SD Card using ES File manager and the others. The other problem is After deleting folder from internal SD Card Storage capacity do not change. I delete 1 GB data but capacity SD Card same.

Here is the explanation.

First of all i rooted Android 4.3 and then install Rom Manager Program from Goggle Store to backup my all info. Room Manager did not work normaly and i tought that it was due to KNOX. Then i install Philz Touch Coustom Rom and remove KNOX. Then i tried to backup my all sistem via Philz Touch Coustom ROM and it worked. Everything was normal. When i run the Room Manager i could not find backup file to restore. I checked the internal SD Card storage capacity and i saw that it was about 3 GB less. It means Backup file saved to internal Sd Card but i could not find by Room Manager. I decide to find this backup file using ES File manager and the others. I could not find Backup Folder or any Backup file. I tried to one more time have backup via Philz Touch Coustom Rom and this time choosed backup to external SdCard. It worked normaly and and after booting android i found the file using ES File manager and the others but not Room Manager. Then i decided to copy this folder to internal Sd Card to check will i see the same folder in internal SD Card. I relized that i have not enought capacity in internal sd card after backup which i could not find folder but storege size 3 GB less. Any how i tried to copy but after coping 1 GB capacity was full and could not copy all files. It was interesting that when i deleted the copied file about 1 GB, storage capasity of internal SD Card did not change. It was full.
How can i solve the problem? Internal SD Card full but i can not see saved backed file and after deleting file capacity do not change.

Best Regards,