By default, when you create an Outlook rule with multiple words in the subject, it searches for one word OR the other. It’s possible to set up Outlook rules to use AND instead of OR by creating multiple rules.
For example, if you want to create a rule that applies to emails with the words “Oulook AND rule“, instead of “Oulook OR rule“, do the following:
Create a rule that applies to emails with the first word (Outlook) and puts those emails into a category or folder or highlights them in some other unique way
Create another rule that applies to emails in the category or folder you made in the first rule and emails that have the second word in (Rules)
The second rule will therefore only apply to emails that have the first word in AND the second, instead of the first OR the second word.
Yes, I agree that this is not a very tidy method and far from elegant, but it works. If anyone finds a better way, please let me know. Hopefully future versions of Outlook will allow people to use AND instead of OR as an optional operand.