All is fish that comes to his net.

The saying portrays someone who treats every opportunity, gain, or person within reach as usable. Like a fisherman who keeps whatever enters the net, such a person does not reject possibilities merely because they are unexpected or unlike the ideal catch. The traditional masculine wording need not limit the interpretation to men.

It can also suggest indiscriminate acceptance driven by appetite for advantage. Depending on tone, it may describe resourcefulness and openness, or criticize a person who is willing to profit from anything without applying much judgment or selectivity.

Use it to comment on someone who eagerly takes every available opportunity or benefit. It suits situations involving indiscriminate acquisition, recruitment, business, or exploitation; context should make clear whether the implication is admiringly practical or disapprovingly opportunistic.