Translation:There are many individuals but only one world.
"There are many persons" is an accepted translation. Therefore, as the plural of person can be either persons or people, then "there are many people" should also be accepted There is some contention over the correct usage of the plural form of person. Generally, most people use the word "people", when speaking of more than one person: the word "persons" is usually only used in a formal manner, such as in legal or literary settings. "People" is generally the preferred plural of "person", but some persons believe there are certain contexts (particularly where there is a specified number of people/persons) where "persons" should be used. However, "persons" is not the generally used plural of person. The New York Times Manual of Style and Usage, for example, states to "use people as the plural of person", while still acknowledging the legitimacy of "persons". Therefore, as "many persons" is an accepted translation, then "many people" should be, also. As "people" is the most commonly used plural of person, it is probably a better translation than the accepted "persons".
Does "cá nhân" mean people? In English, we would say "individuals" when we are emphasising that these are specific people, and not a mass of population. Use of "individuals" indicates that there are significant differences between all of them. Use of "people" combines them into a mass.