Not directly.
You need to combine the two searches into a single search, but each search should have some field that is consistent across all results. This may be as simple as an OR clause, e.g.:
(host=foo) OR (host=bar)
In that case, you can split your chart by series "host".
In more complex scenarios, you might need to resort to something like append to merge the two searches -- then you can artificially add the identifying field, like so:
host=foo | eval series=SearchNumberOne | append [ search host=bar | eval series=SearchNumberTwo ]
This should give you a field called "searchname" in all results -- in your chart, you can then split on "series" to get both distinct datasets.
For more information you might want to refer to How Subsearches Work in the docs, and look for the append and set commands in particular.
Finally, I don't think that charting will let you split by multiple fields. If it won't, and you need that, you can also get creative with eval and string concatenation to generate a new composite field, and split your series on that, e.g.:
| eval series="SearchNumberOne - "+src_ip
