飢不擇食

when hungry, you can't pick what you eat (idiom); beggars can't be choosers / When matters are urgent, don't spend time choosing alternatives.

(bound form) hungry

no; not so / (bound form) not; un-

to select / to choose / to pick over / to pick out / to differentiate / to eliminate / also pr. [zhai2]

to be picky (food)

to eat / food / animal feed / eclipse

to feed (a person or animal)