Perhaps you should try some spelling variations:
su triet » su viet, su tien
ve triet » va trien
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va giao » van giao, va giai, va gia
va hang » van hang, va nang, va lang
hang di » hang doi, hang vi, hang dien

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 ky nang xa hoi. hieu va giao duc va hang di ((su triet) or (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu va giao duc va hang di ((su triet) OR (ve triet)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu va giao duc va hang di ((su triet) or (ve triet))*.