Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thanh di » thanh doi, thanh de, thanh do
qua cao » qua cac, qua ca, qua cai
truc va » thuc va, thuc vat, trung va
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
tuc va » thuc va, tuc xa, thuc vat
di cua » dai cua, doi cua, de cua
cua te » cua tu
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 v nang x hoi. hieu qua cao ((duc va) or (((tuc va) OR (truc va)))) thanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach v nang x hoi. hieu qua cao ((duc va) OR (((tuc va) OR (truc va)))) thanh di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach v nang x hoi. hieu qua cao ((duc va) or (((tuc va) OR (truc va)))) thanh di cua te".
• Adding a wildcard symbol may retrieve word variants: toc sach v nang x hoi. hieu qua cao ((duc va) or (((tuc va) OR (truc va)))) thanh di cua te*.