Eating straight speaking truth.
The meaning is be honest. This follows the pattern of combining the 2nd and 4th words together for the meaning (ngay thật / straight truth). This comes from “Ăn ngay nói thật, mọi tật mọi lành / Eating straight speaking truth, all bad all good” (i.e., be honest about your strengths and weaknesses). This is equivalent to “Open and aboveboard” (i.e., aboveboard refers to hands above the playing table).
Eat immediately staying temporarily.
The meaning can be 1) describing a transient way of living similar to “On the fly” or “On the hoof” or 2) criticizing a reckless way of thinking being in the moment (e.g., YOLO: you only live once).
Use a basket return a scoop.
The meaning is criticizing a person who repays kindness with a smaller gift (i.e., a scoop is smaller than a basket). This is contrasted to “Ăn đấu trả bồ / Use a scoop return a bin.”
Use a scoop return a bin.
The meaning is repaying kindness with a better gift (i.e., “Bồ lúa” or rice bin is larger than a scoop). This is similar to “Do unto others as you would have them do unto you.”
Eat a bite, repay a bite.
The meaning is repaying evil with evil. Eating a bite refers to suffering a wound. This is equivalent to “Tit for tat” and “An eye for an eye, a tooth for a tooth.”
Eat a plum, repay a peach.
The meaning is repaying kindness with a better gift as in “Ăn mận trả đào, ăn quả trả vàng / Eat a plum repay a peach, eat a fruit repay with gold” (i.e., peach is more valuable than plum, gold more valuable than fruit). This is similar to “Do unto others as you would have them do unto you.”
This man is reckless, Drinking and gambling, acting unruly without quitting.