Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thu sach » tu sach, thuat sach, thu hoach
hieu van » hieu va, thien van, lieu va
cam tuc » cam xuc, cam tu, nam thuc
dan cua » dan ca, ban cua, dai cua
dao cua » dai cua, day cua, do cua
va hanh » van hanh, va thanh, va danh
van cam » van nam, van lam, van cau
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
tuc va » thuc va, truc va, tuc xa

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