ORDER BY time consuming

Hi All,

I got a table with about 4.5 millions rows in it which is connected to
another table with about 60 millions rows which are used as keywords for
searching.

I succeded to create fast queries on the first table that finds a row at
the first table which is connected to up to 4 diffrent keywords at the
second table and LIMIT the result to 12 (I want to allow the surfers of
the site to press back and next to see more products so ill make it with
OFFSET).

I want to be able to order my result by a specific column but when I
insert ORDER BY into the query (and any other query that I tried) it
becomes extremly slow, what can I do to solve this problem?

Thanks in advance,
Ben-Nes Yonatan
Canaan Surfing ltd.
http://www.canaan.net.il