Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
duc ban » duc tan, dua ban, duc man
duc van » duc va, duc tan, duc manh
hoa cuu » hoa huu, hoa cua, hoa cau
ho cuu » ho chu, ho cua, so cuu

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

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