Ponds have shores, rivers have banks.
The meaning is describing how everything has boundaries and limits and rules should be respected. This is similar to “Toe the line” (i.e., following the rules) or “Draw the line” (i.e., setting a limit that must not be breached).
Weaver girl and cowherd.
The meaning is describing the separation of husband and wife by comparing them to the Cowherd (Ngưu Lang) and the Weaver Girl (Chức Nữ). The Cowherd, symbolizing the star Altair, and the Weaver Girl, symbolizing the star Vega, were banished to opposite sides of the heavenly river (i.e., the Milky Way). Every year, they are only allowed to reunite on the 7th day of the 7th month of the lunar calendar through a bridge formed by a murder of magpies (crows). This is similar to the star-crossed lovers Romeo and Juliet.
With prayer, there is holiness; with forbearance, there is good.
The meaning is advice on good conduct and often a mantra uttered during the 7th lunar month to ward off evil, because the 7th lunar month is linked to Vu Lan Festival or Ghost Festival (Ullambana Festival) (Buddhist origin). This is similar to “Peace be with you” or “God help/bless you” in Christianity.
Nine persons ten opinions.
The meaning is describing having many people in charge only makes an activity more complicated. A variant is “Lắm thầy nhiều ma / A lot of exorcists many ghosts” where having many exorcists leads to many ghosts. This is equivalent to “Too many chefs spoil the broth” or “Too many generals, not enough privates.”
Scared like a snake on the fifth day.
The meaning is describing a frightened demeanor. The fifth day refers to the fifth day of the fifth lunar month (Tết Đoan Ngọ / Double Fifth Festival). People believe that snakes hide from people who hunt them on the fifth. Another variant is “Len lét như chuột ngày / Scared like a morning mouse.” This is similar to “Scaredy-cat” and “Like a deer/rabbit caught in the headlights.”
Who knows if the raw rice is about the pot or the lid.
This is describing marital problems and not knowing who caused them. A married couple is often referred to as a pot and lid for cooking rice and raw/uncooked rice refers to marital problems. This is equivalent to “Relationship on the rocks” where bickering couples are compared to a ship in dangerous areas.
Who knows which crow is male and which is female.
This is describing something no one cares about or knows about. This is similar to “Not know beans about” or “Beats me.”
National disaster, people’s suffering.
The meaning is describing a disaster in a nation, where the people experience great suffering.
Water disaster from the Heavens.
The meaning is describing a disaster involving rivers and oceans such as floods, storms, or tsunamis that causes immense damage to human life that no one can prevent. This is equivalent to “act of God.”
Dragonflies flying low then rain, flying high then sun, flying normal then shade.
The meaning is when dragonflies fly low rain follows, flying high sunshine follows, and flying normal shade follows. Other variants include “Dragonflies flying low rain floods the ponds, dragonflies flying high rain shower ceases / Chuồn chuồn bay thấp mưa ngập bờ ao, chuồn chuồn bay cao mưa rào lại tạnh” or “Dragonflies flying low rain is coming, flying to the horizons the sun shines brightly / Chuồn chuồn bay thấp mưa sắp tới nơi, bay bổng chân trời thì nắng chang chang.” This is equivalent to “Cows lie down when it is about to rain,” “Rainbow in the morning gives you fair warning,” or “Red skies at night sailors delight, red skies in the morning sailors take warning.”