https://itch.io/game-assets/tag-low-poly/tag-swords
I do not understand the question. Did you miss the second box to chose tags maybe, or the switches to browse/search for assets? Search has one too.
Of course, browsing by tags needs the developer to have used the tags. Like low poly and swords.
Searching, as in using the search box, needs the developer to have used the actual word swords in the title of the asset. Which many asset creators do, unlike game creators. A game with a hero that fights with a sword, usually does not have sword in the title.
Hmm. I think you meant how to combine tag search with title search maybe? You cannot. But for your situation, as asset creators often use the words in the title, you can do this.
https://itch.io/search?classification=assets&q=low%20poly%20swords&type=games