Advice needed

I need some serious help with my dog. She’s doing my head in now. Everything with her revolves around food, she hears a slight noise out the kitchen and instantly goes looking to see if it’s food. We tell her no and tell her to go back in her bed but it doesn’t work for long. Every time my babies done with her breakfast she tries going under the table to clear it and again we tell her no. Everytime we eat she’s staring at us waiting for it. I can’t cope with her, all she thinks about is food. She is a rescue but was rescued at 3m old and homed with me at 6m she’s 4 now. And just to add, she always has access to her food, it’s always down and she even had dinner with us every night.