It has nothing to do with the English. Your explanation is simply not clear enough and we don't get it. You said "if the user clicks this button that the sliding top is coming down" - but where this user should go after click? To specific section? Because if that's what you mean, everything was already explained in the documentation http://themes.muffingroup.com/betheme/documentation/#menu
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if you mean Sliding Top, you can easily enable it under Theme options > Header & Subheader > Extras section.