Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu ve » hieu va, hieu van
duc ban » duc tan, duc van, duc man
dua ban » dia ban, cua ban, qua ban
ve cam » ve cham, ve cac, va cam
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
x hoi » xa hoi, o hoi, x ho
vi su » va su, ki su, oi su
ve su » va su

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach v nang x hoi. hieu ve cam ((duc ban) or (dua ban)) hanh ((vi su) OR (ve su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach v nang x hoi. hieu ve cam ((duc ban) OR (dua ban)) hanh ((vi su) OR (ve su)) triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach v nang x hoi. hieu ve cam ((duc ban) or (dua ban)) hanh ((vi su) OR (ve su)) triet*".