h.e.n.n.a

And the thing I always forget, I want to ask you, if any of you can tell me where in SVK can I buy henna [not that DM one, I want something better like Hennecolor or sth]. Please, I'm searching and searching and all I can find is henna from DM, I was even given some tips where on svk to buy something  better but when I visited the shop they were not selling it any longer.
I don't want the above mentioned henna because it seems to dye only the already colored hair [that was dyed with a permanent haircolor lots of months ago] and not doing anything with my original color [ok, maybe a tiny litlle something..but its not enough]...which is like...its job! And I have tried to leave it for quite a long time on my head, and still it doesn't look like it should.
It looks like this :...so, any ideas? :))