TWO THRILLERS this month, and three novels that could be loosely described As novels of search ? for the past, for the self (or for both past and self). South Africa and Kenya there is very little about Canada in this lot ? are the setting for William Schermbrucker's Mimosa (Talonbooks, 320 pages, $12.95 paper), a quest for the mother who died during his childhood. Addressing her as "you" throughout, a device I found too forced, too mannered, even at times irritating, he builds up scenes from his mother's life, sometimes from material provided by surviving relatives and friends, at other times, though he doesn't always make this clear, from his imagination. (Otherwise how would he know what she ate while travelling to take up a position as a nurse in Kenya?) 'Me result is often moving, occasionally (as in his reconstruction of the double jilting, unknown to her children, that preceded their mother's marriage to their father) almost as exciting as a detective story. At times, however, since each event, even the most minor, is given equal space and the style is unvaryingly flat and unemphatic, the effect is prosaic, even dull (as what life isn't in patches?). This is an unusual concept for a novel. But is the quest successful? Only partly, I feel.

The places and the times and the glimpses of history live, the woman sought for only now and then, in flashes.

In Kevin Roberts's Tears in a Glass Eye (Douglas and McIntyre, 162 pages, $14.95 paper) a young man sits in a lonely shack in British Columbia, trying to come to terms with his Vietnam experiences. The book is tightly and neatly written, in the form of notes made by this young man, who is alone except for a cockatiel that "talks" and a young woman employed by a crisis centre who is trying to educate and straighten him out. The young man, whose early innocence, not to say ignorance, is a bit hard to credit, in view of his present literary style, stumbled upon the bodies of some young American civilians who had clearly been murdered by their own side, not killed in military action. Eventually we learn why they were killed ? though the hero and his friend destroyed the papers they found on the bodies, they did save one letter,. which he, as the sole survivor, finally gets round to reading ? and that his fear that "the authorities" will track him down and punish or even kill him, as we have been expecting ever since the book's first sentence, is groundless. He is ready now to settle down with his girl and to free the cockatiel (which never did say anything very sensible or to the point).

Lisa Herman's Bourgeois Blues (McClelland & Stewart, 256 pages, $26.95 cloth) gives us "Snow," a young Toronto girl who celebrates her graduation from high school by running away to San Francisco, for the reasons people ran there in 1969. In no time at all she has lost her virginity (as she'd planned to do), with someone so unimportant that he never appears or is mentioned again, and gets a job selling encyclopedias door to door. This leads to some amusing if not particularly novel sales?boosting scenes, with everyone chorusing "The world is what we want it to be" and such slogans. Snow is a divided girl, at times convinced that she is "special, magic," at others obsessed by the fear that her failure to feel deeply about the Vietnam War and the Holocaust proves her a Nazi. An affair with her sales boss, at first so romantic and so promising, goes very bad, her room?mate puts her out. She moves in with a homosexual,, the one real friend she's found, and gets a job making porno films. Now she need no longer feel guilty, she believes; she can suffer, at least in thought, with the world's victims. This is a very young book. Like many first novels, it ends a little too quickly, somewhat before it should, and much of the dialogue is cardboard, but there is considerable liveliness in the writing and an attempt at least to deal with a human theme of some complexity in a fairly subtle way.

Of the thrillers John Lawrence Reynolds's The Man Who Murdered God (Viking (Penguin), 257 pages, $22.95 cloth) is the more ambitious and the more satisfying. The scene is Boston. A police team of a Jew and an ex?Catholic atheist are assigned to investigate the first of what proves to be a series of seemingly disconnected police?killings. We watch the murders as they take place and gradually learn more about the young murderer. Each of the various parishes and schools is described quite deftly in small space but though Reynolds has done his best?to personalize his police team by giving the atheist a dying ex?wife whom he visits and making the Jew the peace?maker when the diocese appoints a priest to assist with the investigation, they remain thin, mere mouthers of tough talk. In fact the one real character in the book is the empty?headed mother of the young murderer. And when we eventually learn the reason for the youth's hatred of the priesthood, though we accept the experience as personally devastating, it doesn't seem quite enough, too obvious perhaps, Too bad.

Skywatcher, by Winona Kent (Seal Books, 256 pages, $4.95 paper), takes us to Vancouver and the northwest United States, Robin, the youngest son of the hero of a television spy series, is given a toy robot, seemingly at random, by a woman who soon afterwards jumps or is pushed to her death. The ?toy proves to contain a film, which is sought by the Russians and by the leader of a U.S. cult, both of whom hope to use the directions it gives for modifying satellite "dishes" so that they will transmit as well as receive messages, for their own purposes. Though the attempt to link real espionage with TV espionage is interesting and considerable work has been done on the plot to keep it moving ? there's a great deal of to?ing and froing, several abductions and a number of savage beatings and torturings ? the lack of any sharp characterization makes it difficult to sort out who is on which side, who merely a spy and who a double agent. A quick read this, for those who want no more than that.