Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
nang hoi » nang noi, nang hoc, nang ho
van phan » van phong, van thanh, luan phan
loai su » loai sau, lai su, loai tu
va phan » va phat, va phap, hoa phan
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
hieu su » hieu sau, tieu su, hieu so
hoi hoi » hoi hoc, hoc hoi, hoi doi
ty nang » ky nang, ty xang, ty hang

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 ty nang hoi hoi. ((hieu su) or (hieu va)) cau truc ((va phan) OR (van phan)) loai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang hoi hoi. ((hieu su) OR (hieu va)) cau truc ((va phan) OR (van phan)) loai su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang hoi hoi. ((hieu su) or (hieu va)) cau truc ((va phan) OR (van phan)) loai su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang hoi hoi. ((hieu su) or (hieu va)) cau truc ((va phan) OR (van phan)) loai su triet*.