I have an custom Check object that is a detail of Opportunity and another custom object, Arrangement. The procedure for creating these objects is to go to opportunity and create "New Check". To populate the Arrangement field, the user clicks the search icon to pull up the Lookup Dialogs, select "All Fields" and search by a name.
The problem is that it only pulls up related Arrangements from last year (our business model has a very distinct annual cycle and all opportunities and arrangements belong to a given 'year'). Thus if I search for 'Name' I see all of Name's arrangements from 2016, but neither of his 2 for 2017.
If, on the other hand, I search for the arrangement's name (A0000XXX), it appears. Thus I can find the Arrangement I am looking for, but it will not show up with an All Fields search, but that does return results for previous years. I do not know of any real distinction between previous year arrangements and current ones.
EDIT: I had time to dig deeper and this same thing happens on any object that has a lookup to Arrangement. It will find 2016 Arrangements but none of the 2017 ones from a search, but they will show up when it first opens showing recent Arrangements.