div over div but both div will active on same time

[CesyTapsDrype]

There are two separate div on same position.First div is image slider with left/right button and select buttons of slider images.Second div is search box over the banner.But when i use z-index over any div, the above div is active but another below div is not active. Ex. If slider banner is above, it is working fine. Left/right button and select buttons. But below search box is showing but not active.Please do the needful...