If the target in K5 must contain "XXXX", then:
=IF(ISNUMBER(LOOKUP((9.99999999999999E+307,SEARCH("XXXX",K5)),"next step",K5)
If the target in K5 must NOT contain "XXXX", then:
=IF(ISNA(LOOKUP((9.99999999999999E+307,SEARCH("XXXX",K5)),"next step",K5)
Note that these will not distinguish between XXXX and XXXXX.