Perhaps you should try some spelling variations:
sach tru » sach truc, sach thu, sach tu
thu sach » tu sach, thuat sach, thuoc sach
tru nang » tra nang, tri nang, truc nano
hieu ve » hieu va, hieu van
ve cac » va cac, vien cac
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
tu van » tu 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: thu sach tru nang x hoi. hieu ve cac ((xuc va) OR (luc va)) dinh ((vu van) or (tu van)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach tru nang x hoi. hieu ve cac ((xuc va) OR (luc va)) dinh ((vu van) OR (tu van)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach tru nang x hoi. hieu ve cac ((xuc va) OR (luc va)) dinh ((vu van) or (tu van)) triet".
• Adding a wildcard symbol may retrieve word variants: thu sach tru nang x hoi. hieu ve cac ((xuc va) OR (luc va)) dinh ((vu van) or (tu van)) triet*.