Try it with an apostrophe. I tried an exact match of [l'p] and a phrase match of "l'p" and both showed for searches on l,p -- in an AdGroup where those letters had no significance, go figure.
Of course you run the risk of showing for searches on the 2 character phrase with people using different (or no) punctuation in their searches so you may get some impressions that you don't want. With few exceptions, AdWords ignores punctuation.
Israel
Yes, I wondered the same thing Vanderbolt did about your last comment.
Sujan, for your odd phrase, you may want to go to Tools¦Keyword Tool and see what other searches your combo will turn up for. The "l,p" hypothetical example you gave turned up a lot of odd searches.
Be sure to go into the drop-down list marked "Show Columns" and add "Keyword Popularity" to show you the frequency at which those other odd combos were searched. Many of them look like what I type when I fall asleep in front of the keyboard ;)
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When I tried some of my "normal" keyword phrases, it returned an "XML Request Error" several times possibly because of some delimiter used in the raw search that wasn't being stripped before the "similar keyword" was passed to a query.
When I'd get that error message, BTW, it would sit endlessly until you clicked the "Get More Keywords" a few more times and endured a few more instances of the error message.
If the data is accurate, it has the potential to be somewhat useful.
Israel