Jurisdiction

Out of the three defendnts are residing within the jurisdiction of the court, hence the court has got jurisdiction to try the suit.

out of three two defendants residing within the jurisdiction of the court, its a matter related to trade union frist defendant is Registrar trade union 2 & 3 are person from union

suit for what? it is recovery of money suit or suit regarding property.

after that only it will be clarified.

trade union office bearers dispute , plaintiff filed a suit  and 

defendant no 1 Registrar trade union, decree of declaration in his favour to declare that defendant no 2 and 3 are in illegal possession of all original documents and other articles of the union .also seek mandatory injection against no 2 and 3 to hand over the entire records

Yes. the court can try the case. The registered office of the union is within the limit of the court jurisdiction and others are members of that union. The mater in dispute is  also regarding documents. 

in this case the office of registrar is under the juridiction of court ,but the office of union out of juriduction of court