Then I'll suggest as the others already have that you examine the nasty little "black" or "off-the-books" fighting which occurred in Laos, Cambodia, and elsewhere.
"Advisers" from both the US and USSR were active and both the US and USSR took great care to both maintain a fig leaf for their advisers' operations while deliberately "ignoring" the presence of the other guy's advisers.
While it was in the best interest of either the US or USSR for that fighting to occur, it was not in the best interest of the US or USSR for it to become widely known that their "specialists" had fought one another.
Thanks for the info.