Perhaps you should try some spelling variations:
thanh lap » thanh san, phan lap, thanh hai
thu sach » thuat sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
va thanh » gia thanh, ban thanh, va tinh
su triet » su viet, su tien, ve triet
tu sach » su sach, te sach, tu cach
co hoi » co hoc, co loi
lap su » lap du, lap tu, lai su
o hoi » o hoc, o hai, o hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) OR (thu sach)) ky nang ((o hoi) or (co hoi)). hieu van pham duc va thanh lap su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang ((o hoi) OR (co hoi)). hieu van pham duc va thanh lap su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang ((o hoi) or (co hoi)). hieu van pham duc va thanh lap su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky nang ((o hoi) or (co hoi)). hieu van pham duc va thanh lap su triet*.