I have ran into an issue that has followed me from Outlook 2010 to the newest version of Office365 Outlook 2016.
A user is required to search for numerical data for order numbers and such. Searching for words in the search bar works fine. However, searching for numbers just does not work. Even though I can see a mail in the inbox with the string of numbers I searched for, it states that no results were found! We have rebuilt the search cache I also found a technet article which states the advanced search function would be a workaround for this.. it is not as this does not work either.
Has anyone ran into a fix for this issue?