Hi ivrtejaswi,
The journal entry will show on the GST Report (eg GST Detail Report) as long as a) one line has a GST code associated with it or b) the lines have different GST codes assigned. If there is no GST code on the journal at all, it will not display on the report. Similarly, if the entry has the same GST codes on both lines it will not show as these codes zero or balance each other out.
-Kass
