Word-level bigrams/trigrams in tsvector - Mailing list pgsql-hackers

I'm wondering how I can store word-level bigrams/trigrams in a tsvector that I can query against. I was expecting the final query to match "the air" and return the one tuple to me.

postgres=# create table docs (a tsvector);

CREATE TABLE

postgres=# insert into docs (a) values (strip('''the air'' smells ''sea water'''::tsvector));

INSERT 0 1

postgres=# select * from docs;

               a                

--------------------------------

 'sea water' 'smells' 'the air'

(1 row)

postgres=# select * from docs where a @@ to_tsquery('''the air''');

 a 

---

(0 rows)

Thanks, Alan