Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va triet » va thiet, va trien, ve triet
xuc van » duc van, luc van, vuc van
te sach » toc sach
xuc ban » duc ban, cuc ban, quoc ban
dinh vu » dich vu, dinh ve, dinh cu
hieu ve » hieu va, hieu van
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
ve cam » ve cham, ve cac, va cam
o hoi » co hoi, o hoc, o hai
vu va » vu van, tu va, su va

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) or (te sach)) y nang o hoi. hieu ve cam ((xuc van) OR (xuc ban)) dinh vu va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (te sach)) y nang o hoi. hieu ve cam ((xuc van) OR (xuc ban)) dinh vu va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (te sach)) y nang o hoi. hieu ve cam ((xuc van) OR (xuc ban)) dinh vu va triet".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (te sach)) y nang o hoi. hieu ve cam ((xuc van) OR (xuc ban)) dinh vu va triet*.