Chelsea striker Fernando Torres has been strongly linked with the club, while Manchester City's Edin Dzeko and Real Madrid forward Alvaro Morata have also been subject of speculation.
Inter Milan general director Marco Fassone has confirmed that Fernando Torres is one of the players they are interested in.
Thohir also name-checked Torres - as well as Dzeko and Morata - and insists improving their strike-force is high on Inter's agenda.
"We will buy a European level striker," the club owner told Indonesian TV station Bola.
"There are many candidates that we are considering.
"Dzeko, Torres and Morata? These are not only rumours, I hope that one of them comes to us."