As other have mentioned, cold symptoms are hard to fight, because it's your body fighting against virus.
For shore throat however I find this infusion/decoction amazing.
Natusor 3 - Farinol - Infusiones | Amatusalud
http://www.soligaia.es/Natusor-3-FAR...-SORIA-NATURAL
Maybe you can't find the exact same product where you live, but the ingredients are:
*Agrimonia eupatoria,
*Althaea officinalis, root
*Salvia officinalis, leaves
*Thymus vulgaris, steam
*Plantago lanceolata whole plant
In my opinion its flavour is terrible (my boyfriend however loves it), it taste like frankincense. But it really helps me when my throat really hurts.
Lemon juice and honey is another popular beverage against shore throat, but it's not good if you have mucus.
You also can take steam baths with some eucalyptus oil, to help you breath and smooth the throat.
My grandma used to leave a chopped onion over her bedside table because she said that it help her breathe, but I 've never tried tbh. It sounded odd.