How triggers are called when we have two triggers?
If I am understanding your question correctly, you are looking for the sp_settriggerorder system stored procedure (http://msdn.microsoft.com/en-us/library/ms186762.aspx). Through the used of this stored proc you can set whether a trigger fires first or last (or undefined, and any trigger in between first and last has no guaranteed order). 

(Note: this only applies to AFTER triggers, and cannot be used with INSTEAD OF triggers)