how can I leave my URL as usual ?

[acyk]

Dear sir

I need your help

because we are using Traditional Chinese for Title , so the wiki set my URL to a nightmare code for it

Can you help me to set the wiki URL to real simple one , for example threads id = 12345

http://iphone4.tw/forums2012/showwiki.php?id=12345

[pegasus]

It's not possible to change all wiki URLs like this, without doing something else.

First check vBulletin Options > VaultWiki: Server Settings > Enable UTF-8 Support for URLs? and make sure it's turned on.
You will have to use VaultWiki > Wiki URL Manager > Rebuild All URLs after this.

If this is still no good, you will have to make new wiki forums that are Island-type wikis, and move all your articles there. Island wikis use numbers in the URL, but also mean that your wiki is setup in a strange way that might be hard for users.
You still need the non-Island Default wiki forum in order for VaultWiki to work.