Perhaps you should try some spelling variations:
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 cam » va cham, va cac, va cao
xuc xa » tuc xa
buc xa » tuc xa
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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 cam ((xuc xa) or (buc xa)) hanh ((vi cua) OR (di cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu va cam ((xuc xa) OR (buc xa)) hanh ((vi cua) OR (di cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu va cam ((xuc xa) or (buc xa)) hanh ((vi cua) OR (di cua)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu va cam ((xuc xa) or (buc xa)) hanh ((vi cua) OR (di cua)) tre*.