Hi,
First, I suggest configuring and enabling the index table engine. That will index all the neccessary information, each keyword individually. Once configured, make sure it is enabled.
Then, picking the correct keyword logic is the key. The default logic should be okay for most cases, but I may recommend try a bit more strict variation, such as “AND with exact keyword matches” as primary and an “AND” or “OR” as secondary, whichever fits best: https://i.imgur.com/sgC6Xnq.png
Then adjusting the weight of the keywords. The content keywords are not that important to you, so I would tone that down, and increase the terms weight, something like this: https://i.imgur.com/n8pV1aO.png
That will highly prioritize the taxonomy term keywords, even if the content has a lot of occurences of the given keyword.
