This problem encountered since I moved my server to IIX, which has less bandwidth for international user, and for that reason too, the downstream is too small to download whole WordPress package that used for updating. That’s why, I always get timeout error. So, I’m simply unable to automatically update my WordPress.
However, the solution is actually simple, by increasing the timeout so the download can be completed. Once it is, the updating will going smoothly. So this is how to do it, in manual way.. 🙂