Your question is not totally clear to me. It is difficult to understand what you are exactly doing without giving indications on what is stored in advisors and l3613. What do you have in l3613 ? Is it a single mail ?
Based on what I understood from your question, I would do the following:
Put the following formula next to the name of each advisor:
This will give you the index in the table of the 1st occurence of each advisor. You may then select from that row the minimal number from the subset of advisors you are looking for (e.g. with a minifs function).
The advantage, here, is that you use the wildcard matching from the match function (avoiding nesting 2 search functions). Also, the match will stop at the first occurence of each advisor and will not look till the end of the list when it is not needed. Ultimately, you may assume that there will be a match for all of them and that the new emails will never be parsed, because it is not necessary.
Example of usage:
Please forgive me if I have not fully understood your issue. I hope this will help you anyway in solving your problem.