I am creating an application using Wavemaker with MySQL backend

I am trying to create a HQL where there are no FK's present between tables

Relationship as follows

OrderHeader join OrderDetail on headerID
OrderDetail join ItemMaster on itemID

I can get the first part of the query working, but not sure how to add the third part - How would i join the ItemMaster from here? The OrderDetail table has a itemID field, but I want to join the ItemMaster table to get the itemDescription (red items are fields I want add/join)

When I add the red items, I get errrors

select
order.poID as PO,
detail.lineID as line,
detail.vskuID as itemID,
items.ItemDescription

from OrderDetail as detail

LEFT JOIN OrderHeader as order where order.headID=detail.headID
JOIN ItemMaster as items where detail.itemID=items.itemID

ORDER BY order.poID,detail.lineID