High pass filter, like the name implies allows higher frequencies to pass (reduces the low end) Just the opposite for the low pass filter. dynamic EQ allows you to get a better handle in the sound by allowing you to control individual frequency ranges. This eq usually has a "Q" value which allows you to select the frequency width that each selection will effect.

Try some compression and a little reverb in addition to the ones you mentioned. Also posting an example of your recordings will allow us to hear it and make better suggestions.