[sqlite] Improving text search using LIKE '%string to search%'

[Patrick Peccatte]

I use SQLite 2.8.14 for a documentation application which needs a lot of
text search.
Text searchs are done using somethink like:
SELECT * FROM Texts WHERE CurrentText LIKE '%string to search%';
I use index on every searchable columns.
Response time are acceptable until about 100000 texts stored in database,
but are very very long with 500000 texts in database.
Is exist any method to improve this kind of search ?
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Patrick Peccatte - Soft Experience