The 24-year-old's contract with the Bluebirds expires next summer, and Deila confirmed that the South Korean is one of "two or three" players that could arrive in Glasgow.
"That's a guy we have been talking about but we haven't done anything concrete," he is quoted as saying by Sky Sports News.
"It's not about numbers, it's about quality. If we can get players who can make the team and the squad better, it could be two or three players. But if we don't find that, it could be zero."
Bo-kyung's last Cardiff appearance came in the 3-1 win over Huddersfield last weekend.