Perhaps you should try some spelling variations:
duong trong » dung trong
hanh trinh » canh tranh, hanh chinh
thanh tung » thanh cong
duong cong » dung cong, luong cong, trong cong
hien hanh » dieu hanh
vang thai » dang thai, lang thai, van thai
thai cao » tai cao, thoai cac, thuat cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien hanh - ((hanh trinh) or (thanh tung)) va ((duong cong) OR (duong trong)) vang thai cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien hanh - ((hanh trinh) OR (thanh tung)) va ((duong cong) OR (duong trong)) vang thai cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien hanh - ((hanh trinh) or (thanh tung)) va ((duong cong) OR (duong trong)) vang thai cao".
• Adding a wildcard symbol may retrieve word variants: hoc hien hanh - ((hanh trinh) or (thanh tung)) va ((duong cong) OR (duong trong)) vang thai cao*.