MySQL: Index when joining to tables not being used (Performance optimizing question)

I need to optimize the following query:

SELECT /* [things omitted] */ articles.blogpost_id, articles.id AS articleid
FROM blogposts
JOIN articles ON articles.blogpost_id = blogposts.id
WHERE blogposts.deleted = 0
AND blogposts.title LIKE '%{de}%'
AND blogposts.visible = 1
AND blogposts.date_published <= NOW()
ORDER BY blogposts.date_created DESC
LIMIT 0 , 50

EXPLAIN SELECT gives me the following result:

id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE articles ALL blogpost_id NULL NULL NULL 6915 Using temporary; Using filesort
1 SIMPLE blogposts eq_ref PRIMARY PRIMARY 4 articles.blogpost_id 1 Using where

Why does it first take the articles and then the blogposts? Is it because blogposts have more entries?
And how can I improve the query so that the articlepost can use an index?

Update:
An index is set on blogposts.date_created.
Removing the blogposts.title LIKE condition and the date_published <= NOW() doesn't do anything.

When I remove the "articles.id AS articleid" it can use the blogpost_id Index on articles...
Sounds strange to me, someone knows why? (because I actually need it..)

The new explain looks like this:

id  select_type table   type    possible_keys   key key_len ref rows    Extra
1   SIMPLE  articles    index blogpost_id blogpost_id    4    NULL    6915    Using index; Using temporary; Using filesort
1   SIMPLE  blogposts   eq_ref  PRIMARY PRIMARY 4   articles.blogpost_id    1   Using where

Your where condition blogposts.title LIKE '%{de}%' will cause a full table scan on the blogposts table. It's likely MySQL figures scanning 6915 articles is more efficient.

As to how to improve it, you might add an index on blogposts using the date_created or date_published and add a range the to the where condition (something other than <=NOW())

StackExchange Database Administrators Q#872, answer score: 4