AO3 filtering for either of two (or more) tags
You might have noticed that when you include more than one item in your AO3 filters, the number of results drops drastically. When you include more than one item, you're telling the filter to find fics that have tag A as well as tag B, and the more items you include, the more things you're requiring a fic to have in order to show up in your results.
You're telling AO3 that you only want fics that have all of the things. You're not telling AO3 that you want fics that have any of the things.
This is because the filters use something called Boolean operators. The Boolean operators are: AND, OR, and NOT. You need to use caps for these terms in order for them to function as an operator and not just another word in a phrase.
AND (the one used by include filters) means you want both (or all) of the things
OR means you want any of them or any combination of them
NOT (the one used by exclude filters) means that you want none of them, either alone or in combination
So if Include = AND and Exclude = NOT, then how do you use OR? Use the Search Within Results box. It's near the bottom of the filter menu, right above where you can choose which language you want to read and below where you can choose word count range and completion status etc.
In this box, type the name of the first tag you're interested in, then the name of the second tag and put an OR in the middle. Keep adding OR in between them, and you can stack as many tags as you want - until you get to whatever the character limit is (character, in this case, meaning letter, number, or symbol).
If a tag is just one word, then your filter would look like this:
If a tag is more than one word, then your filter would look like this:
"no beta we die like men" OR "I wrote this instead of sleeping"
You need the quotation marks around multiple words to let the filter know that those words belong together, in that order
If you want to do an OR search for ships, it gets a bit more complicated because of the symbols used in ship tags. For ships, instead of using the name of the tag, it's better to use the tag ID number.
To find the tag ID, tap/click on the ship tag to go that tag's results page (I'm using Frodo/Sam in this example). On that results page, tap on the button labelled RSS feed. That will either open up a new page full of code or download a text file of code. Near the top of that code, you'll see something that looks like:
The tag ID number is the number that appears after /tags/
In this case, the tag ID number for Frodo/Sam is 13674. When I repeat the same process for Frodo & Sam, I get the tag ID number 716913. Then I just need to set up my OR statement and let it know that the tag number I'm providing is a relationship ID:
relationship_ids: 13674 OR relationship_ids:716913
Put that in the Search Within Results box, and I'll get fics with either one of those ships tagged, and I'll also get results with both ships tagged.
Oh! and if you don't know how to find the filters menu, just tap on any tag and then on the button labelled Filters. You won't see this menu on a search results page. However, you can use these same techniques in the search bar at the top of the page or in the Any Field box at the top of the Advanced search page.
