Searching text in a big table

[Sanny Sun]

Hi there,
   I have a big table which has 250000 rows.And each row has a BLOB field
which stores lots of text. When I search text in this table(using the query:
where CONTENT like '%news%'),the searching speed is quite slow. is there
anybody also have such problem? Any ideas about improving the speed of
searching text in big table?

Thanks in advance.

Sanny