The phrase you're asking about is in and refers to a specific genre of adult-oriented folk storytelling or "wari." Specifically, "Eteima" refers to a sister-in-law (brother's wife), and the phrase translates to stories involving that specific relationship.
“Eteima thu nabagi wari, 4 better” is a : Don’t invent worry where none exists — peace itself is already an improvement. eteima+thu+nabagi+wari+4+better
Given the lack of clear connections between these terms, let's explore a hypothetical scenario where they could be related. The phrase you're asking about is in and