Treatment for nose sores depends on the cause and the
location. If they're deep in the nose you probably need an antibiotic. Using a good aerosol (to get far enough in) saline spray several times a day can help wash away bacteria. They're only recommended a couple of times a day though.
If the sores are on the edge you can use a saline gel (such as Ayr) if the problem is related to dry winter air, or try a topical cortisone cream twice a day if the skin seems broken and more than just dry.
Yellow liquid sounds like an infection. If it was my problem I'd get rid of it with a topical antibiotic, as you have done, and then continue to treat with saline gel. I use saline gel most nights in the winter. It keeps buildup from forming and keeps me from picking and rubbing unconsciously.
Of course if home treatment doesn't or the infection gets worse you need to see a doctor! You may need oral antibiotics for a while.