What studies did you do in NZ? And what job have you gone into? This can make a difference to the application you can make next, as, if the job is on the Immediate Skill Shortage List
http://skillshortages.immigration.govt.nz/, you will not have to show proof of advertising by your employer.
Here's the mention of the Essential Skills work visa.
http://www.immigration.govt.nz/migra.../requirements/
If you have a job offer from a New Zealand employer and do not fall under one of the categories for specialist workers below, you may apply under the Essential Skills work category. The employer will need to show that no New Zealand citizens or residents are available to do the job, either by:
showing that the job is included in one of the Essential Skills In Demand Lists; or
providing evidence that they have genuinely tried to find a New Zealand worker to fill the position.
In addition, you must be appropriately qualified by training or experience to take up the position. See the full list of requirements.