I'm not totally sure what you mean but I guess you mean that you "plugged" the holes? What you can do is to heat up the solder pad from the top side and then stick the wire in when the solder has melted. You should have a bit of solder on the solder-tip when you do this to get good heat transfer. Also the square pads tends to take a little longer to heat up. Some tips in this post as well.