Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
duc thang » duc tan, duc hung
thanh lap » thanh san, phan lap, thanh hai
duc tang » duc tan, tuc tang, duc tung
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
ve cao » va cao, ve bao, ve cac
cua tu » cua tuc, cua su, cua te
cua cu » cua chu, cua cau, cua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ty nang xa hoi. hieu ve cao ((duc tang) or (duc thang)) thanh lap ((cua tu) OR (cua cu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ty nang xa hoi. hieu ve cao ((duc tang) OR (duc thang)) thanh lap ((cua tu) OR (cua cu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ty nang xa hoi. hieu ve cao ((duc tang) or (duc thang)) thanh lap ((cua tu) OR (cua cu))".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ty nang xa hoi. hieu ve cao ((duc tang) or (duc thang)) thanh lap ((cua tu) OR (cua cu))*.