Some segments left untranslated after Pre-translate

Hello,

I pre-translated a file with Language Cloud but it has left some segments untranslated.

For this particular project, about 1.5K out of 30K was left untranslated.

Every segment must be pre-translated with AT so the whole file can be outsourced to an external translator who does not have access to Language Cloud.

Do you have any suggestion?

I believe this issue has not been raised here before, but it has, please kindly help me find the known solution.

Thank you.

Rami Kim