I assume you mean wintercreeper euonymus, Euonymus fortunei, an evegreen groundcover. If this is the case, then there are couple herbicides that are grass specific that you should be able to spray over the top of the grouncover and kill the grass but not harm the wintercreeper. The two consumer types have either the active ingredient of Fluazifop-P-butyl (fusilade) or sethoxydim.

Products availabe with fusilade include Syngenta Fusilade II, PBI Gordon Ornamec Over the Top Grass Herbicide, and Ortho Grass B Gon, and others.

Products containing sethoxydim include Bonide Grass Beater II, Ferti-Lome Over the Top Grass Killer II, Hi Yield Grass Killer, Monterey Grass Getter, and others.

It is important to make sure your groundcover is properly identified before applying any herbicide. You can send images or you can contact the Oklahoma County OSU Extension Center for assistance - https://extension.okstate.edu/county/oklahoma/. The products mentioned above are quite safe to use on many different broadleaf ornamentals, but it is important to make sure of what yours is and to read and follow all label directions of the product you purchase.