Dear Anusha
Mark tried to help a little bit. As mentioned in my answer: the correct use of BAPI BAPI_BUS1077_GETDETAI is explained in many threads.
Before you can use this BAPI you need to understand the data model of EHS.
Based on proper "flagging" of the "import" parameter you can get result data which is linked to ESTRH etc.
E:G: links mentioned below might help
BAPI_BUS1077_GETDETAIL EHS: Read Specification - Function - ABAP - SAP
SAP ABAP Function Module BAPI_BUS1077_GETDETAIL - SAP Datasheet - The Best Run SAP
https://www.consolut.com/en/s/sap-ides-access/d/s/doc/F-BAPI_BUS1077_GETDETAIL
So you should think here in "tables" but in "business objects". Some of the return parameters clearly represent content of tables as ESTRH, ESTRI, ESTVH etc. So you achieve the goal by using the right input parameter.
The use this BAPI depends on your business need (which data ro present etc.)
You need to keep in mind that if you use the BAPI direct you have no option of "refinement" of inquiry as in CG02; so the most important topic to consider is: PERFORMANCE !!! If you have a database in place with 500.000 specifications and lots of data records the input paramter of the BAPI are the "key" factor to get results in "short" time.
C.B.