i'm new to android development and i want to set up my android studio but when i about to download sdk .. there's error :

Download finished with wrong size. Expected 127315313 bytes, got 33431605 bytes.
Done. Nothing was installed.
Preparing to install archives
Downloading Android TV ARM EABI v7a System Image, Android API 21, revision 1
Resuming Android TV ARM EABI v7a System Image, Android API 21, revision 1 download at 177015040 (65%)
Download finished with wrong size. Expected 93883708 bytes, got 34745961 bytes.
Done. Nothing was installed.
Preparing to install archives
Downloading Android TV ARM EABI v7a System Image, Android API 21, revision 1
Download interrupted: Read timed out
Downloading Android TV Intel x86 Atom System Image, Android API 21, revision 1
Resuming Android TV Intel x86 Atom System Image, Android API 21, revision 1 download at 108171390 (37%)

please help me.. thanks