Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thu sach » thuat sach, thuoc sach, thu hoach
van pham » san pham, van phan, van phat
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
cau tren » cu tren, dau tren, ca tren
cua viet » ca viet, hoa viet, cua vat
tu sach » su sach, te sach, tu cach

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 (tu sach)) ky nang x ho. hieu van pham duc va thanh di ((cau tren) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (tu sach)) ky nang x ho. hieu van pham duc va thanh di ((cau tren) OR (cua viet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (tu sach)) ky nang x ho. hieu van pham duc va thanh di ((cau tren) or (cua viet))*".