Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
cau tren » cu tren, dau tren, ca tren
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
va pham » van pham, va phat, va phan
va phap » va phat, ban phap
nang o » nang co, nang ho, nang ro
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. lieu ((va pham) OR (va phap)) duc va thanh di ((cau tren) or (hoa viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang o hoi. lieu ((va pham) OR (va phap)) duc va thanh di ((cau tren) OR (hoa viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang o hoi. lieu ((va pham) OR (va phap)) duc va thanh di ((cau tren) or (hoa viet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang o hoi. lieu ((va pham) OR (va phap)) duc va thanh di ((cau tren) or (hoa viet))*.