Tai vi chữ ngầm la chữ tieng Viet nen khong co o trong Chữ Nôm. Nhu vay Nguyen Trai phai su dung chữ Han chữ "ngâm" de thay the cho chữ ngầm. Nhu vay ý nghĩa cua thủ vĩ ngâm là "ý nghĩa ngầm" (Hidden Meanings -- Metaphors) or "Topsy-turvy" Things are upside down.
This poem was written or about his situation in 1408. It is read from the bottom line to the top line. He is in Nam Kinh with the other Vietnamese. He has hidden his identity from the Chinese -- he could become a mandarin for the Chinese but doesn't want to. The Dai Ngu Dynasty (Nhà quen) is in disorder and no one represents it. Things are difficult because Vietnam is so small so no (one) can make merit. There is no one to guide Dai Ngu so times are tough. The idea (of "khoi nghia") is beckoning and he wants to go. He is barely surviving and he is still stuck in Nam Kinh.