Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
sach thu » sach thue, sach thieu, sach tham
va triet » va thiet, va trien, ve triet
thu nang » thi nang, thu hang, thu bang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cam tuc » cam xuc, cam tu, nam thuc
dan vai » dan va, dan vat, dang van
den vai » den va, den vay, den vi
dan tai » van tai, dan thi, han tai
ve cam » ve cham, ve cac, va cam
tuc va » thuc va, truc va, tuc xa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach thu nang xa hoi. hieu ve cam tuc va ((((dan vai) OR (den vai))) or (dan tai)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach thu nang xa hoi. hieu ve cam tuc va ((((dan vai) OR (den vai))) OR (dan tai)) va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach thu nang xa hoi. hieu ve cam tuc va ((((dan vai) OR (den vai))) or (dan tai)) va triet".
• Adding a wildcard symbol may retrieve word variants: hoc sach thu nang xa hoi. hieu ve cam tuc va ((((dan vai) OR (den vai))) or (dan tai)) va triet*.