Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
giau cua » gian cua, gia cua, dieu cua
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
cac lop » cac hop, cac loai
sach ty » sach y, sach tu, sach thu
via cua » gia cua, gian cua, rija cua
cac co » cac cong

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty nang xa hoi. hieu van ((cac lop) or (cac co)) van minh ((via cua) OR (giau cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang xa hoi. hieu van ((cac lop) OR (cac co)) van minh ((via cua) OR (giau cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang xa hoi. hieu van ((cac lop) or (cac co)) van minh ((via cua) OR (giau cua)) te".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang xa hoi. hieu van ((cac lop) or (cac co)) van minh ((via cua) OR (giau cua)) te*.