"We're conscious we have to win on Monday. Perhaps we lacked a bit of daring in the last third of the pitch against the Ivory Coast. We have to go for goals," Eduardo told reporters.
"But we played against a strong team, well organised and physically powerful. In this competition we've seen matches are complicated as teams are well organised. Sometimes even a 1-0 win is like a rout," he added.
Cristiano Ronaldo came close with a long-distance drive that hit the post, but Portugal otherwise created few chances in a cautious approach against the African side.
If Ronaldo's terrific effort had hit the net it would have been his first goal for Portugal in a competitive match for two years. The forward's plight is part of a longstanding goalscoring problem for the Portuguese.
They limped to the finals after failing to convert stylish play into results and were forced to beat Bosnia in a playoff. Brazil-born striker Liedson was brought in to help, but after a promising start the poacher has gone quiet.
Simao, their top scorer in the qualifiers with five goals, is set to regain his place against the Koreans after Danny failed to repeat his fine displays in the friendlies.
The aftermath of the draw in the opener included Deco's criticisms of coach Carlos Queiroz's strategy. The playmaker has apologised and is expected to start on Monday.
With that controversy settled, the focus in the Portugal camp is on how to defeat the North Koreans who put in a stubborn display in their 2-1 defeat to Brazil on Tuesday.
Asked if he could name five North Korean players, Eduardo said: "No, they are very difficult to pronounce. But the important thing is to know what they are capable of and what their main weaknesses are, so we can take full advantage."
