Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
hieu va » lieu va
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
tu cua » hu cua, vu cua
dan va » doan va, dan ca, ban va
tu ca » tu cac, tu can, tu cay

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