Drop Down box limits amount of data

[rfm1966]

Hello ... I have a drop down box pulling values from a item database into a purchase order database.. What I find is that I don't get all the data... Ex- products from a-z in items database... In drop down box in purchases.. I see only products from a-s.. t-u-v-w-x-y-z is missing..The drop down is in a portal.. Hope this is clear.. thanks