When you write to a text file, LabVIEW keeps a pointer along with the reference while you have the file open. So after you write "test" to the file, your new pointer is now at location 4. When you Read after that, it reads from pointer 4 and on.
Use the Set File Position function in the advanced palette to read from position 0.
I think you need to set your file position back to zero after the write. You're reading back from the position after your write which is probably empty.
