You can share the file by bluetooth like this:
Intent sharingIntent = new Intent(Intent.ACTION_SEND);
Uri screenshotUri = Uri.parse(picURI);
File file = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/Sample.txt");
sharingIntent.setType("text/plain");
sharingIntent.setPackage("com.android.bluetooth");
sharingIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(file));
startActivity(Intent.createChooser(sharingIntent, "Share file"));