everyone may have different item preferences for each hero, I suggest to you use recommend builds from global top of the heroes and of course it will be much easier
Moskov stunt max duration is 2 second by using his 2nd skill to enemies and hit a wall, there is also Guides by one of Forum user MOSKOV on his FULL POTENTIAL!? .
There is also Nana Guide, Item, and playstyle in here Nana Guides .besides also can use top global players build, give it a try.
Personally Id use the builds of Top players as they ofcourse take a long time to practice them and Its guaranteed that itll work properly. There may be a few Items that may not work for you but it would be a good learning experience.