It is estimated by fans that the population of Planet Vegeta before Frieza's destruction was 10,000 Saiyans.
The question is knowing that the Dragon Ball universe is huge, why won't the Saiyans colonize planets and grow their population?
It didn't have to be something massive like the Imperium of Man which has over 10 quadrillion humans or the Star Wars galaxy which has over 100 quadrillion sentient beings.
My doubt is why the Saiyans didn't colonize a dozen planets to grow the population or even increase the population of the planet Vegeta?