Because we need some documents may require him to coordinate, if he is not very clear coordination can not, or could affect the work, this could be a problem.
Because we need some documents that may require him to coordinate, it may be a problem if he doesn't know it very clearly, otherwise it may affect the work.
Because we need some documents that may need him to coordinate. If he is not very clear, he can't coordinate, or it may affect the work, which may be a problem.<br>