K.
Always nurse BEFORE you feed your daughter solids. Drink plenty of water. Some women swear by eating oatmeal.
Make sure you alternate which side she starts nursing on, and that she nurses from both sides each feeding. If she eats from both side and still isn't done, do NOT give her a "chaser" bottle - instead put her back on the first side. If she still seems hungry but is too frustrated to try and get more milk out (because you're near empty) take a little break and offer hear a breast again in another 15 or 30 minutes. Your milk supply will only increase if it is stimulated to do so. Make a habit of offering her the breast every 2 hours or so to bring your supply back up. If you want to use the pump, you'll be most effective if you pump AFTER you feed her, as this will simulate a very hungry baby.
At 6 months old she really shouldn't be eating very much food - certainly not so much that she cuts back on her nursing I think. Maybe just 1 meal per day. You might consider temporarily (for 2 weeks or so) cutting way back on her "food" and just nursing her a ton to get your milk supply back up and then reintroduce the food more slowly and with better timing (after you nurse her).
Herbs don't work immediately, so keep taking the fenugreek - it can't hurt and it may just take a little more time to kick in.