How to use the ~ (includes) filter operator?

When I've used commas in Filters previously, I've had to specify the field after each comma, for example "filter=internalId~LMD1234567,clear:*" or "parentId:1,fullPath~Template" so I assume you may need to do something like "filter=internalId~LMD1234567,internalId~LMD7654321". BUT I would have expected it to attempt to search for an alert that has internalId of LMD1234567 AND LMD7654321 which would never exist. So I'm rather surprised it even get one result.

In my testing I get no results for "filter=internalId~LMD1234567,LMD7654321" but I get the first result when I use "filter=internalId~LMD1234567,internalId~LMD7654321", which I didn't expect. So I'm not exactly sure what is up. I do see that the doc doesn't show internalId as a valid filterable field but does seem to work anyway without commas.

Playing around and watching how to portal does it (F12 in browser, network tab) I was able to get a working solution using:

 /alert/alerts?needMessage=true&filter=_all~"*LMD1234567 OR LMD7654321*"

But really it looks hacky and undocumented. I would suggest just putting in two separate API calls for each LMD# and combine in code or get all the alerts and filter via code.