Hi Shankar,
Kindly check below SAP Note.System landscape for Prd, Qas and Dev must be the same architecture.
TREX Master (talent) and TREX Master (E-recruitment) should be different server.
Search Engine Service(SES)
SAP Note 1254901 - SES for custome project on TREX search
Embeded Search(ESH)
SAP Note 1249465 - TREX 7.1:Installing TREX for Embedded Search
SAP Note 1628169 - TREX 7.10 for Embedded Search - Landscape restriction
Regards
Mohamad Firhad Samuri