What is the significance of grass according to Torah’s perspective or what is that I can learn from seeing grass (deshey) ?

Shalom, Thank you for your question. While it is true that according to some Jewish teachings, a person should look for spiritual meaning in all they see – much of the meaning to found must come from a personal understanding. That is, the meaning and message one person may see in the world, will be different for another person. None the less – here are the words to a famous Hebrew song, based on the teachings of the Chassidic Rabbi, Rav Nachman of Breslav – Know that each and every shepherd has his own tune. Know that each and every grass has its own song. And from the song of the grasses the tune of the shepherd is made How beautiful, how beautiful and pleasant to hear their song. It's very good to pray among them and to serve Hashem in joy And from the song of the grasses the heart is filled and yearns. And when the the heart is filled by the song and yearns for the Land of Israel a great light is drawn forth and goes from the Land's holiness unto it. And from the song of the grasses the tune of the heart is made. Transliterated: Da l'kha shekol ro'eh ve ro'eh yeish lo nigun m'yuchad mishelo. Da l'kha shekol eisev v'eisev yeish lo shirah m'yuchedet mishelo. Umeishirat ha'asavim na'aseh nigun shel ro'eh. Kamah yafeh, kama yafeh vena'eh k'sheshom'im hashirah shelahem. Tov me'od l'hitpaleil beineihem uv'simchah la'avod et Hashem. Umeishirat ha'asavim mitmalei haleiv umishtokeik. Ukh'shehaleiv, min hashirah mitmalei umishtokeik el erets yisra'el. Or gadol azai nimshakh v'holeikh mikdushatah shel ha'arets alav. Umeishirat ha'asavim, na'aseh nigun shel haleiv. Here are the two sources in Rav Nachman’s original teachings that this song is based on – Know that every shepherd has a unique melody (nigun) according to the grasses and the place where he herds, for every animal has a grass unique to her that she needs to eat. Also a shepherd isn't always in one place, and according to the grasses and the place where he herds, so he has a nigun. For every grass there is a song (shirah) which it speaks, that this is the aspect of Perek Shirah, and from the song of the grasses is made the nigun of the shepherd. And this is the secret of what's written, "And Adah bore Yaval, he was father of all who sit in tents and herd, and the name of his brother [was] Yovel, he was father of all who grab the lyre and the harp." For just when there was in the world [for the first time] a shepherd of cattle, just then there were musical instruments. And so it is with David the king, who "knows music-playing" and therefore was a shepherd...And this is the aspect of "From the edge/wing/kanaf of the earth we heard songs (z'mirot)"--[it means] that songs and nigunim come out from the "wing of the earth", for by means of the grasses growing in the earth/land a nigun is made. And since the shepherd knows the nigun, by means of this he gives strength to the grasses, and so there is something for the animals to eat...and there is pasture for the animals/...And also the nigun is good for the shepherd himself, since the shepherd is always with the animals, [because] it would be possible for them to draw [down] and lower the shepherd...to the aspect of the spirit of animals [if not for the nigun]....And know that the king has every nigun in completeness...for the nigun is made from the growth of the land. ~ LM 2:63 Know that when a person prays in the field, then all of the grasses/plants together come into the prayer, and they help him, and give him strength within his prayer. ~ LM 2:11 I hope this is of some help. Blessings.