So you want to know what debt securities are doing when you're trading stocks? Seriously?
Some facts for you:
The S&P 500 comprises 377 NYSE stocks and 128 Nasdaq stocks
The NYSE Tick and A/D indicators are based upon 3132 securities, of which about 2000 are operating companies and the rest are all sorts of security types (various exchange traded products, debt securities, hybrid debt-equity, closed-end funds, rights, warrants, preferreds etc).
Let me put it another way....
Let's say you're going shopping for vegetables because you own a restaurant. As part of your decision making process for buying those vegetables, you use an index, which is made of up of 60% vegetables (many of which you never buy) plus 40% of the index is for cosmetics.
However, you insist on using this index because it's somehow representative of what you're buying.