KOIL-100 cannot be verified against its exchange. Apparently, KOIL 100 is not available for investing at the moment. Please verify the symbol is currently traded on Tel Aviv Stock Exchange. If you still believe the symbol you are trying to look up is valid please let us know and we will check it as soon as possible.
Please see also Stocks Correlation. Please also try Portfolio Optimization module to compute new portfolio that will generate highest expected return given your specified tolerance for risk.