Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
tinh thai » sinh thai, tinh toan, tinh chat
thai cua » than cua, tai cuc, tri cua
sach ky » sac ky, sach y, sach ty
van cac » van hac, van cau, dan cac
van bac » van ban, van bao, van hac
va tinh » may tinh
cua te » cua tu
x hoi » o hoi, x ho, 5 hoi

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 ky nang ((x hoi) OR (xa hoi)). thien ((van cac) or (van bac)) nuoc va tinh thai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang ((x hoi) OR (xa hoi)). thien ((van cac) OR (van bac)) nuoc va tinh thai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang ((x hoi) OR (xa hoi)). thien ((van cac) or (van bac)) nuoc va tinh thai cua te".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang ((x hoi) OR (xa hoi)). thien ((van cac) or (van bac)) nuoc va tinh thai cua te*.