The club made a £90m offer for Costa at the turn of the year which the Spaniard was allegedly prepared to take.
Reports of a training ground-up between Antonio Conte and the forward also surfaced, though Chelsea sought to play down such speculation and insisted their top goal-scorer would not be going anywhere.
However, Shu Yuhui, owner of Tainjin Quanjian, has said the club are still eyeing a move for Costa.
Yuhui told Sina Sports: “I can only say that we are still working on the deal [to sign Costa]. And we have already made contacts with several players.
"We have high standards [in buying foreign players] and those players prefer top clubs such as Bayern Munich and Real Madrid.
"It's safe to say that we have the same transfer targets as those illustrious clubs.
“We may have to pay bigger price because our club are now competing with Real Madrid and Bayern Munich.”