How to deal with people who speak another language?

When you try and get support or work with someone whose primarly language isn't yours, what are some of the best ways to get the message across w/out?

Example 1: I hired someone on vworker and can't get the point accross. I thought they knew what the job was but now I know they don't. I've told them step-by-step and even drawn examples only for them to still be confused.

Example 2: Support w/ a fairly large company I work speaks/writes English well but something is always lost in communication. I am always blamed for the issues then after several emails, once it was two weeks, they finally get it or decide to fix it instead of blaming me when they decide I'm not going away. Many times I've had to make a video.

So how do you deal with barries like this? How do you know it's a barrier and not a "they will go away" issue?

Frustrated.

Garrie

PS When I know I'm working this people who speak english as a 2nd language I give more details than I normally would but in smaller chunks. I also have someone read it to see if it makes sense to them because at times I forget people cant read my mind and leave parts out.