I have LG LHD45EL Dehumidifier this humidifier and it's not collecting any/very little water, even after we had 1-week of rain and seepage in teh room it's being used it. Is there some type of filter/part that needs to be cleaned?

Cleaning the air intake filter certainly won't hurt. Also, check the humidity setting. You may have it set to low. In addition, it wouldn't hurt to check the drain tube or drain hole (whichever one your unit has) that's just above the bucket. You'll see it once you remove the bucket. It may be clogged and is not allowing the water to drain properly. Using a 18" long plastic Zip Tie or something similar (No wire coat hangers) that will comfortably fit into the hole ... Carefully and gently run it as far as you can into the drain hole or tube. The tricky part is when you reach the bend in the tube. So, tread carefully. Once you have it inserted as far possible, as you rotate the Zip Tie, slowly pull it out. Rotating it, will loosen any debris. Be prepared for water to follow.

If none of the above solves the problem, the compressor in the dehumidifier may be low on refrigerant gas and will need to be recharged.

Hope this helps you troubleshoot and solve the problem.