Perhaps you should try some spelling variations:
thien cau » hien cau, khien cau, thien hau
thien cac » hien cac, thieu cac, trien cac
va trien » va truyen, va thiet, va tuyen
su triet » su viet, su tien, ve triet
sach ky » sac ky, sach y, sach ty
da tinh » dac tinh, dao tinh, dam tinh
tinh di » tinh doi, trinh di, tinh da
nang xa » nang x, lang xa, nang ma
te sach » toc sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang xa hoi. hieu ((thien cac) OR (thien cau)) tac da tinh di ((va trien) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang xa hoi. hieu ((thien cac) OR (thien cau)) tac da tinh di ((va trien) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang xa hoi. hieu ((thien cac) OR (thien cau)) tac da tinh di ((va trien) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang xa hoi. hieu ((thien cac) OR (thien cau)) tac da tinh di ((va trien) or (su triet))*.