Yes, if you have sqlite3, you can query the eventlogger database.
From xterm:

sqlite3 /home/user/.rtcom-eventlogger/el-v1.db "select remote_uid ,free_text From events where outgoing = 0;"

Shows all numbers and text for incoming messages.

And if you know one word which is in your spam messages, you
can filter the results by this word. If your spam messages include the word "SPAM" for example:

sqlite3 /home/user/.rtcom-eventlogger/el-v1.db "select remote_uid ,free_text From events where outgoing = 0 and free_text like '%SPAM%';"