Steaua claimed earlier this week that a deal for Chiriches to move to Tottenham was close to being sealed with the Romanian side resigned to losing the highly-rated defender.
Villas-Boas is keen to bolster his defensive options after selling Steven Caulker to Cardiff City and after admitting his interest in Chiriches he joked that they may lose him as they had done when Chelsea stole in to sign Willian from right under their noses.
"Vlad Chiriches, there is an interest in the player," said Villas-Boas. "Maybe somebody steals him as well!
"I'm telling you we have looked to strengthen our backline with the departure of Steven Caulker, last year we had Younes [Kaboul] injured for the season but we had five, so we are looking for the position and we are going to go ahead with our re-strengthening."
Villas-Boas refused to criticise Willian for snubbing Tottenham to move London rivals Chelsea instead.
"The answer that I want to tell you is Willian made a choice to join Chelsea and the only I can wish him is good luck because he is a person I have a good relationship and he has decided to join another club," added Willian.
"Good luck to him ... he made a choice, that he feels is important for the development of his career, good luck to him."