I am trying to pronounce all words of namaz with proper tajweed. but its difficult sometime and due to keeping concentration on tajweed that no mistake occurs.. my concentration from the meaing of words of namaz goes …

what is good should i concentrate more on meaning or tajweed ?

sometime if concentrate on meaning mistake occurs in tajweed as in arabic there are different words of Z
like zal , zwad , ze , zoi etc
and in our indian language there is single Z voice word

You know the meaning already, so you should continue practicing your tajweed. After much repetition it will become natural for you and wont require such concentration. At that point the meaning will become the primary focus.