Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
quoc va » nuoc va, duoc va, quoc gia
va chat » van chat, va phat, cao chat
y nang » ky nang, ly nang, v nang
loc va » hoc va, luc va
nang o » nang co, nang ho, nang ro
de cua » le cua, dieu cua
te cua » tue cua, le cua
o hoi » co hoi, o hoc, o hai

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 y nang o hoi. lieu va chat ((quoc va) or (loc va)) hanh ((de cua) OR (te cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang o hoi. lieu va chat ((quoc va) OR (loc va)) hanh ((de cua) OR (te cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang o hoi. lieu va chat ((quoc va) or (loc va)) hanh ((de cua) OR (te cua)) tre".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang o hoi. lieu va chat ((quoc va) or (loc va)) hanh ((de cua) OR (te cua)) tre*.