Perhaps you should try some spelling variations:
thuat sach » thuat lanh
thuat san » thuat toan, thuat song, thuat lanh
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
va tinh » may tinh
bai cua » ban cua, dai cua, hai cua
nang o » nang co, nang ho, nang ro
o hoc » co hoc, mo hoc, so hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thuat sach) OR (thuat san)) ky nang o hoc. hieu van pham duc va tinh ((bai cua) or (bai ca)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (thuat san)) ky nang o hoc. hieu van pham duc va tinh ((bai cua) OR (bai ca)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sach) OR (thuat san)) ky nang o hoc. hieu van pham duc va tinh ((bai cua) or (bai ca)) tre".
• Adding a wildcard symbol may retrieve word variants: ((thuat sach) OR (thuat san)) ky nang o hoc. hieu van pham duc va tinh ((bai cua) or (bai ca)) tre*.