I am updating a SQL SELECT statement to have an embedded SELECT statement in it but the two embedded selects are returning empty. Any idea why this is not working?

SELECT a.MODELNAME, d.STARTTIME, d.ENDTIME, d.BATCH, d.VALUE,c.USERLABEL, b.USERLABEL, e.UNIT, a.GI,
(SELECT x.USERLABEL from RESOURCES x, RESOURCETYPE y
WHERE x.pkuid=a.pkuid AND x.RESOURCETYPEID=y.PKUID),
(SELECT w.USERLABEL from RESOURCES w, KQI z
WHERE w.pkuid=a.pkuid AND w.PKUID=z.BREAKDOWNRESKEY_FK)
from KQI a, RESOURCES b, RESOURCETYPE c, COMBINEDSNAPSHOTS d, COMBINEDKQIMODEL e
where d.kqi_pkuid = a.pkuid
and b.PKUID = a.RESOURCEID_FK
and c.PKUID = b.RESOURCETYPEID
and a.MODELNAME = e.MODELNAME;