Pokertracker help with combining sessions

[octop]

I have had pokertracker for a few weeks and would like to do the following:
Under sessions PT lists every session for each site with the room and date. I would like to try and combine several sessions together ( for example Im working off the party bonus and would like to combine the 9 or 10 rooms Ive played clearing this bonus into one session.)

Does anybody know how to do this?