What is the four-word idiom to describe ancient poetry?

1. The four-word words describing the true feelings of the world are sincere and sincere. Brothers and sisters in the depths of the ocean are affectionate and helpful. They share weal and woe, take care of each other and treat each other sincerely. Life and death are inseparable. Blood is thicker than water, so I advise you to have a glass of wine in the west. There is no reason to go out of Yangguan. —— Wang Wei's "Send Yuan to Twenty Shores Xi" sails alone in the blue sky, only looking at the Yangtze River. -Li Bai's Farewell to Meng Haoran on the Way to Yangzhou is not as good as Wang Lun's. -Li Bai's "A Gift to Wang Lun" Mochow has no bosom friend in the road ahead, and there is no bosom friend in the world. -Gao Shi's "Don't move big" The moon is now full of the sea, and the end of the world is at this time. -Zhang Jiuling knows each other far and near, while Wan Li is still a neighbor. -Zhang Jiuling met with rain after a long drought, and met an old friend in another country. -Wang Zhu knows the truth in adversity.