Do somebody know some program where I can use my gpu's to force password to encrypted document ?
Try AccentPPR. The searching speed is high and there are various features to vary the range of searching (dictionary mutation according to the preset rules, position mask -
YouTube channel).
As for GPU. Nobody can offer good support - it is difficult to implement the protection algorithm in Adobe PDF on GPU. GPU exists for Adobe 9 that is never used, as a matter of fact (Adobe faced an epicfail with hashing iteration in it but it was fixed quickly).
We wrote about it all - the running speed and peculiarities of protection of various versions of PDF.