I am a vegetarian. i cannot take fish.so please tell the other sources of omega-3 fatty acids?

Many sources: Look to chia seeds, flax seeds, hemp seeds, beans, seaweed, and leafy greens. Still your best bet are from the seeds!

Flaxseed oil: You can use flaxseed oil if you feel you need omega 3.

Plant sources: Plant sources like flax-seeds. Soybean, canola, wheat germ and walnut oil all have a decent amount of omega-3's, but much higher levels of omega-6 fatty acids and that is a favorable ratio.