Here in the States, we use a spinosad spray. Neem oil helps, but is slow. Modified pyrethroids can prevent infestation, but don't cure entrenched problems.

there are sprays available in the garden centres sug as bug clear. some will target thrips others don't. so read the label with care. what plants are affected?

clove of garlic added to 1 litre water dilution

1 cigarette of tobacco in 1 litre water dilution

The garlic spray will repel thrips as they try to migrate to your plants, but may not stop entrenched colonies. The nicotine from the cigarette may be effective, especially if you add a little soap to the solution, but you stand a risk of infecting the plants with tobacco mosaic virus. Also a good reason to not smoke when gardening. :)