One left join works, VERY similar one doesn't

[bubbles]

Here is my table structure:
Table: User
Fields: UserId,FirstName,LastName,FriendCount

Table: Network_User
Fields: UserId,NetworkId

Table: Network
Fields: NetworkId, Network

Table: Keyword_User
Fields: UserId,KeywordId

Table: Keyword
Fields: KeywordId, Keyword

This query works correctly:

SELECT u.UserId,u.FirstName,u.LastName,u.FriendCount FROM `User` u
LEFT JOIN `Network_User` nu ON nu.UserId = u.UserId
LEFT JOIN `Network` n ON nu.NetworkId = n.NetworkId
WHERE n.Network = 'Purdue' ORDER BY u.FriendCount DESC

It returns 2 rows.

This one does not:

SELECT u.UserId,u.FirstName,u.LastName,u.FriendCount FROM `User` u
LEFT JOIN `Keyword_User` ku ON ku.UserId = u.UserId
LEFT JOIN `Keyword` k ON ku.KeywordId = k.KeywordId
WHERE k.Keyword = 'weeds' ORDER BY u.FriendCount DESC

It returns an empty set, where it should return 2 rows like the other one.

I know the correct data is in the tables for it to return.

I noticed that

SELECT * FROM `Keyword` WHERE `Keyword` = 'weeds'

Also fails.
While

SELECT * FROM `Network` WHERE `Network` = 'Purdue'

Works fine
Any idea why?

 

[bubbles]

Fixed.

Correct queries were

SELECT u.UserId,u.FirstName,u.LastName,u.FriendCount FROM `User` u
LEFT JOIN `Network_User` nu ON nu.UserId = u.UserId
LEFT JOIN `Network` n ON ( nu.NetworkId = n.NetworkId AND n.Network = 'Purdue' )
ORDER BY u.FriendCount DESC

SELECT u.UserId,u.FirstName,u.LastName,u.FriendCount FROM `User` u
LEFT JOIN `Keyword_User` ku ON ku.UserId = u.UserId
LEFT JOIN `Keyword` k ON ( ku.KeywordId = k.KeywordId AND k.Keyword = 'weeds' )
ORDER BY u.FriendCount DESC

Had to specify my where column in the joins as well.