Garkin pointed me helpfully to this information at my addon.
I tried figuring out how it would work correclty with the plurality forms of item links and i couldn't figure it out how it works properly.
For example
the m: would define the plural form of the item
Code:
zo_strformat("<<1>> <<2>> <<m:3>>", player, quantity, itemlink)
the question i couldn't figure out is how to define the plural form of the item based on the quantity. The strings in zgoo display just generally use the single form.