Suffixes of this type indicate the speaker's attitude toward the noun, or how sure the speaker is that the noun is being used appropriately.
This suffix indicates that the noun is being used in a false or ironic fashion. Saying rojqoq so-called peace, rather than simply roj peace, indicates that the speaker does not really believe that peace is legitimate or likely to endure.
This suffix indicates that the speaker is pretty sure the object referred to by the noun is accurately described by the noun, but has some doubts. For example, if the scanner on a Klingon ship senses an object, and the officer reporting the presence of this object assumes, but is not yet sure, that the object is a vessel, he will probably refer to the object as DujHey an apparent vessel, rather than simply Duj vessel.
This is the counterpart of -Hey. It indicates that there is no doubt in the speaker's mind as to the accuracy of his or her choice of words. Once the Klingon officer referred to above is sure that the object the scanner has found is a vessel, he might report the presence of Dujna' a definite vessel, undoubtedly a vessel.