Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve chat » va chat, van chat
duc van » duc va, duc manh, duc phan
lai cua » hai cua, lai chau, thai 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 ty nang xa hoi. hieu ve chat ((duc van) OR (duc tan)) anh ((lai cua) or (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. hieu ve chat ((duc van) OR (duc tan)) anh ((lai cua) OR (dai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. hieu ve chat ((duc van) OR (duc tan)) anh ((lai cua) or (dai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. hieu ve chat ((duc van) OR (duc tan)) anh ((lai cua) or (dai cua)) triet*.