Comparing tsvector results

Hello,

I'm trying to implement a keyword-based search on my database.

I have some text input (Say, "The A or B and C with D") and a list of
keywords ("B","X","Y"). I want to identify which keywords are present in
the text input. I also want to use a thesaurus to process the text input,
since the keywords have synonyms (for example, "The A : X").

As far as I understand, the only way for me to process text input with a
thesaurus would be to use tsvector / tsquery; or at least this is the
fastest way.
Is it possible to retrieve the tsvector from the text input, then retrieve
the tsvector from the keyword list, and identify which words are present in
both?

Thank you!