It sounds like you're referring to the (The Thinkers Collection), a renowned Brazilian series of philosophy books published by Abril Cultural (and later by Nova Cultural). The "long story" behind this collection is fascinating, involving politics, education, and a publishing phenomenon in Brazil during the 1970s–1990s.
It also represents a golden age of popular publishing in Brazil – when a media conglomerate risked printing Marx under a dictatorship, sold it to the masses, and changed the country's intellectual landscape. colecao pensadores
Here is the of Coleção Os Pensadores . 1. The Context: Brazil Under Dictatorship (1964–1985) In the late 1960s and early 70s, Brazil was under a military dictatorship. Universities were purged of "subversive" professors, and many philosophical works (especially Marxist ones) were banned or hard to find. Censorship was rampant. It sounds like you're referring to the (The