Will these prducts help me achieve straighter hair.?

Ok I have a 20 dollar conair flat iron. Since my hair isnt too bushy and big its like flat then wzy it straightens nicely. But It still gets messy later on. I bought some products and I wonder if they will help me get a better looking head of straight hair. Right now I use the herbal essences shampoo and conditioner the dangerously straight one. Right now I just bought some Tresseme Heat Protectant for when I use my flat iron. I also bought the herbal essences dangerously straight mousse. Will that have any effect and whats the proper way to use it. Lastly I bought the Aussie leave in conditioner. Its called Aussie Hair Insurance Leave In Conditioner. I also have some Nexus styling liquid. Can I get some nice straight hair with these products?