Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
phap duc » pham duc, phan duc, phap doc
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
dat tren » dat trong, dua tren
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu va » lieu va, hieu qua
va phap » va phat, ban phap
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 ty nang ((o hoi) or (x ho)). hieu va phap duc va thanh di ((dat tren) or (hoa viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang ((o hoi) OR (x ho)). hieu va phap duc va thanh di ((dat tren) OR (hoa viet)).
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang ((o hoi) or (x ho)). hieu va phap duc va thanh di ((dat tren) or (hoa viet))*.