Radhey Radhey,
The meanings of the terms you asked about are:
Karuna: compassion, kindness (in its highest form, this is not based on attachment, but on an understanding that the same God we are worshiping resides in the heart of every soul)
Maitri: friendship (a true friend is willing to tell his friend when he is doing something wrong, even of he is unhappy to hear the criticism)
Sahansheelta: tolerance, forbearance (the strength to bear unpleasant people, words or situations without feeling angry or perturbed)
Santosh: remaining happy with what one has (one can be active in the world, but without hankering for the accumulation of material possessions and achievements; the one who is santosh takes loss and gain as it comes, without being affected by the ups and downs of life)
Kshama: forgiveness (by remaining angry with someone, we only hurt ourselves; forgiving someone else is really just a way of relieving ourselves of a burden)