Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va triet » va thiet, va trien, ve triet
hieu ve » hieu va, hieu van
truc va » thuc va, thuc vat, trung va
dinh su » hinh su, dinh cu, dinh du
y nang » ky nang, ly nang, v nang
ve cam » ve cham, ve cac, va cam
luc va » duc va, tuc va, loc va
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y nang x hoi. hieu ve cam ((luc va) or (truc va)) ((dinh su) OR (dinh so)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang x hoi. hieu ve cam ((luc va) OR (truc va)) ((dinh su) OR (dinh so)) va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang x hoi. hieu ve cam ((luc va) or (truc va)) ((dinh su) OR (dinh so)) va triet".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang x hoi. hieu ve cam ((luc va) or (truc va)) ((dinh su) OR (dinh so)) va triet*.