...........they don't do much to remove the clog so you add some more .......and more...........And still you got the clog......
First-timer.......Why not check the drains under the sink and remove the P-trap (use a bucket) and the stopper.......you'll cetainly find some strange lost objects and a big hair clog and WHO knows what else..............EEEWWWW!!!!!!....
You'll also get familar with the house and it's "Bowels" before you're forced to do it when the sinks full of water and nothing is working right.........
Remember to tackle this on a day when the home center/hardware store is open .......In case you need to replace any of the parts...........