Mancini has regularly indicated he wants to sign attacking players, who prefer to play out wide, in the January transfer window and has already brought in Lukas Podolski on loan from Arsenal.
But the 50-year-old coach wants at least one more winger for the second half of the Serie A season and believes Inter's comeback after half-time away to Juve on Tuesday proved why width is critical to his preferred 4-3-3 formation.
Inter were rather narrow in midfield with Mateo Kovacic and Hernanes flanking lone striker Mauro Icardi until Podolski was brought on in the 54th minute.
"We had more control of the wide areas and they found it harder to push up, that's all," Mancini said, according to Inter's website.
"After that we went on to create some good chances."
Xherdan Shaqiri has regularly been linked with Inter and could be exactly the kind of wide attacker Mancini wants.
Asked again about the possibility of signing the Switzerland international from Bayern Munich, Mancini made it clear he is interested in Shaqiri but cautioned that a lot of work needs to be completed before any potential transfer or loan can be completed.
"I don't know if we'll be able to do things quickly, although as a coach that's what you always want," Inter's coach said.
"Quality players are always useful. Look at Podolski - even though he's not at his best, he gave us and he'll give us a big hand.
"You need good players to win in football. You can't win trophies without them."
While the draw on the road against the Serie A leaders was an impressive result for 11th-placed Inter, Mancini was left frustrated by his team's first half when Juve dominated.
"In the first period we struggled to get the measure of them," he said.
"We only had about ten minutes when we did quite well, then after the break we did much better.
"It's a decent point but I'm not completely happy because games last 90 minutes and in the first 45 we didn't play as well as we should."
