I've got a Gmail email filter rule set up to prevent email from various senders from going into spam.  Here's a simplified version of the rule:Matches:from:(abc.org.nz|def.nz|westpac|mailman|ird.govt|mybank|contact)Do this: Never send it to SpamAs you can see, to keep it short and more generalised (not too generalised so far), I have not listed entire email addresses.So far the above rule seems to be working for everything listed except mybank, which still allows emails from office@mybanksavings.co.nz to go into spam.Is this because the filter doesn't match on partial words (alphanumeric strings?), or what?I had a quick look here, but it didn't seem to go into sufficient detail:   https://support.google.com/mail/answer/6579?hl=enSo if you know of a link to support whatever you say, that could also help.
Gmail filter on partial words
gmail;gmail filters
Gmail search doesn't support wildcards, partial words, or regular expressions. By extension, then, neither do Gmail filters. (Some information from Google Support.)@example.com will work because @ is a word separator. But @example will match @example.com but not @examplexyz.Some related questions here:Gmail filter with regular expressionsFilter field to contains wordGet rid of Russian junk from my Gmail