Perhaps you should try some spelling variations:
thien van » thi van
van tham » van thanh, van tuan, van chat
tham duc » pham duc, tham du, than duc
tan hanh » tan thanh, tang hanh, toan hanh
su triet » su viet, su tien, ve triet
sach ty » sach y, sach tu, sach thu
cao hoi » cau hoi, co hoi, cao hoc
hanh ki » hanh vi, hanh ky, hanh kien
sac ky » cac ky, sai ky
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sac ky) or (sach ty)) nang cao hoi. thien van tham duc tan hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sac ky) OR (sach ty)) nang cao hoi. thien van tham duc tan hanh ki su triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sac ky) or (sach ty)) nang cao hoi. thien van tham duc tan hanh ki su triet*.