Your specimen looks like glossogobius, but I'm not certain with species

@Herminie Palec Palla. Thank you for your comment. Indeed, it shows an affinity towards Glossogobius. But the caudal fin colouration is what is throwing me off. Let's see what the other experts opine.

G. giuris is the known species to occur in Indian waters in certainty. It looks very much like the species mentioned, apart from the ocellatus at the base of the caudal fin which normally is not this much pronounced in juveniles or subadults.

Abhishek Mukherjee Thank you for your comment.

This can be the Glossogobius giuris. We also can find the specimens in Vietnam as well.

Two species of Glossogobius are found in Indian region, G. biocellatus and G. giuris. My observation on the fish species is that it could be G. giuris because of characteristics like 1) Body elongated and somewhat depressed, 2) Body pale rather than dark, 3) Branchiostegal membranes attached to sides of isthmus, 4) Iris without process in pupil, 5) Dorsal, pectoral and caudal fins seem to be mottled with dark spots, and 6) If the species attains a length of about 30 cm.

@Nguyen Quan Van Thank you for your comment.

@Munira Nasiruddin Thank you for your detailed explanation.

I agree with Glossogobius giuris.

Two additional species of the genus have been reported from India, G. kokius and G. minutus, but the specimen in the photograph agrees best with G. giuris.

The former Glossogobius biocellatus is now classified as Psammogobius biocellatus.

@Roland Fricke Thank you so very much for your answer.