Not to mention the table scans this probably causes:

...

AND (u.FirstName LIKE '%' + 'asdf' + '%' OR

u.LastName LIKE '%' + 'asdf' + '%' OR

JobTitle IN ( SELECT JobID

FROM Jobs

WHERE

OrgID = 4 AND

Job LIKE '%' + 'asdf' + '%') OR

u.Email LIKE '%' + 'asdf' + '%' OR

u.UserName LIKE '%' + 'asdf' + '%' OR

u.Department LIKE '%' + 'asdf' + '%' OR

u.AlternateID LIKE '%' + 'asdf' + '%' OR

u.AlternateID2 LIKE '%' + 'asdf' + '%' OR

u.AlternateID3 LIKE '%' + 'asdf' + '%')

...