Is the yellowish discharge on the seventh day considered menstruation or not, and is the slight discharge seen on the eighth day considered menstruation?

The fatwa we adopt is that yellowish and brownish discharges are considered menstruation if they occur within the period of one's regular cycle or if they are connected to blood. If your regular cycle is six days, then any additional discharge is not originally considered menstruation. If you see purity, perform ghusl (ritual bath). If your regular yellowish or brownish discharge occurs on the seventh day, do not consider it menstruation unless it is connected to blood.