Hi drhadidy , install from Synaptic "LXAppearance" , from there you can change gtk themes, Icons and Fonts.
I will install as follows.
Download file > Open Console as Root > Type Thunar > Select file and the extract option in usr/share/themes or Icons usr/share/icons.
Then from LXAppearance, you can select the themes or icons that you have.
Nodoka themes in Synaptic is very good.