Hey there - that's not much information to go on, and we're all still coming to terms with the demo ourselves .. but in previous games that would be indicative of either a tactical issue or a team-talk issue.
On the tactical front, if you're using the tactics creator wizard, have you tried the starting strategy "Control"? That focuses on a patient build-up, that sort of "pass it around the perimeter until the defense is out of shape, then find the incisive pass" approach, while keeping enough of a defensive shape to help prevent the quick breakaway. If that isn't working, you might try the starting strategy "Attacking", which will be a bit more direct - chancing losing possession more often but also pressing to create more turnovers. Its more vulnerable to the counter-attack. I'd recommend starting with "Control" if you're heavily favoured, and shifting to "Attacking" in the final ten minutes of the first half if its still nil-nil.
Team-Talk wise, if you have a highly professional team, "I expect a win" is the right approach. If you have some fragile-ego me-me-me players, you might go with "We can win this", but you need to give the individial team-talk "I expect a performance" to those professional enough to handle the pressure. Simply saying "We can win this" may yield an uninspired performance. Likewise at halftime, if you're heavily favoured but still drawing nil-nil, you do need to be down on the team to inspire a second-half showing.
There will be much more information on both these topics in the Tactics and Training Tips forum.