Romeo doesn't want to leave the Capulet's property so, he ditches his friends and hides out in the orchard behind the Capulet house.
Benvolio and Mercutio try to find him. Unaware that Romeo now has the hots for Juliet, they shout lots of filthy things about Rosaline in hopes that Romeo will emerge to curse them out and defend Rosaline's honor. No such luck.
Benvolio says "Go then, for tis in vain / To seek him here that means not be found" and they head home.
We interrupt this program for a helpful reading tip: Worried that your copy of the play divides scenes differently than we do here? Don't trip. The division of acts and scenes from Romeo and Juliet varies depending on which edition of the play you're reading. Some editions of the play (like the Folger edition, the Riverside Shakespeare, and the MIT online edition) cut off Act 2, Scene 1 at the end of Benvolio's line (quoted above) and give the famous balcony scene its own section (Act 2, Scene 2). Some other editions (like the Norton Shakespeare) include Romeo and Juliet's famous balcony scene in Act 2, Scene 1. Now back to our program.