Thanks for the quick reply.
1) Yes, the title actually contains the word 'The'. The full title of the post is 'The Servant (1963)'
2) Case doesn't matter, it bugs with both.
3) Fulltext search is off and unused.
4) Keyword logic is the default – AND.
5) Show exact matches is off. Partially typing the second word (without the 'the') does return results also, for instance typing 'serv' returns it in the results.