I think I can relate to your problem...
I too was pretty mystified when the cards started to show different and un-relevant meanings to my questions. But I found out a secret!! The Cards also sometime just address the issue that is most important at that moment, even if its different from what you asked the cards to show you.
I also agree with Dan181, perhaps you just THINK that the spreads are not working for you. Write down the spreads, because something that could happen later on in your day might actually make you say," Wow, that earlier spread that I couldn't figure out, now makes sense!" That's how I am all the time
Also don't stress over it. Remember to always keep an open mind too
If you believe in your cards and use them with good intentions, they will always help.
*Also maybe you need to spiritually cleanse your cards too.
(Meditate for a while, then envision golden light spreading from your aura, through your hands, bathing the cards while you shuffle them.) or Google a procedure